Question: i found that the company i work for is putting a backdoor into mobile phones

Response:
It is right to worry; some people advise removing the backdoor completely.
Just because the company won't use it, doesn't mean someone else won't find it and use it.
By definition your company is knowingly shipping a product with a serious security vulnerability.
If they don't see it as a big deal, you're not asking them the right question.
All you can do is communicate the risk in a way that the business area can understand.
This was reported in China's ZTE Ships Smartphone with Backdoor to MetroPCS.
Although sometimes required by law (insist on internal documentation to that effect), you should seriously consider going to some governmental or regulatory authority with this, just to protect yourself, for example, CVE.
You can go on pastebin and make a full and comprehensive security advisory (cover your tracks).
Some people counsel against immediate whistleblowing.
Beforehand, you should hire a very skilled lawyer and be prepared to lose a lot of time and money, or even the job.


Question: how to switch or close the new split terminal pane?

Response:
You need to press Shift-Cmd-D on your keyboard.
Alternatively, if you are using OS-X shortcuts, the combination ⌘ Shift ⌘Command D will accomplish the same task.


Question: ios untrusted developer error when testing app

Response:
If "Profiles & Device Management" is not visible on your device, you may need to reinstall the app or obtain the correct profile from an MDM or another enrollment service.
Additionally, there's an Xcode solution involving the deletion and reinstallation of profiles and the app.
Specifically, you can navigate to "Window > Devices" in Xcode, remove the undesired profiles from your device, and then proceed to delete and reinstall the app.
For iOS 14.4 and Xcode 12.4 users, you can address the problem by going to "Settings," then "General," followed by "Device Management," and clicking on "Apple Development" to trust an app.


Question: how can paypal spoof emails so easily to say it comes from someone else?

Response:
Anyone can falsify email addresses, including the sender information, and PayPal uses certain SMTP headers related to the message header rather than envelope headers to handle email delivery appropriately.
While it is technically possible to spoof email addresses, PayPal is not actually doing so.
It is also noted that Gmail supports DKIM, which can be used to verify the authenticity of emails from PayPal.


Question: how can i stop applications and services from running?

Response:
If an app does something you disapprove of, such as running in the background or at startup, the quickest solution is to uninstall it.
Reaching out to the app's developer can lead to a fix, allowing you to continue using the app normally.
Many applications close completely if you exit them using the Back button instead of the Home button.


Question: how can i tell if a green text message has been delivered?

Response: If the bubble is blue, the message has been sent as an iMessage, and iMessages have a built in delivery report that will tell you it has been 'delivered' or 'read' when the message gets delivered/read, but a regular SMS (when it is green) doesn't provide these options; if you have jailbroken your device, there is an SMS Delivery Report repository in Cydia.


Question: where is the apk file downloaded from google play store?

Response:
.apk files are downloaded and stored somewhere in a subfolder on your device called /data.
However, in order to access this folder, you will need to root your device.


Question: external drive does not mount after plug off without eject

Response:
If you are trying to mount a hard disk and it appears in the disk utility but cannot be mounted, you could try mounting it as read-only using the command `diskutil mountDisk readOnly /dev/diskx` to access your data, especially if there's a chance that the disk's partition table is corrupted.
In severe cases where the partition is indeed corrupted, you may have to format the hard drive.
Before taking that step, it can be useful to repair the volume for any errors using the disk utility or terminal commands.
You should also go to Launch Pad, open Disk Utility, select the disk that won't mount, and attempt to repair it.
Another possible solution is to eject the disk first and then try to mount it again, which may work without errors.
Furthermore, if you have tried various commands, such as mounting and unmounting, and they fail, you could unmount and eject the disk, then reconnect it to your computer.
Sometimes, using a Windows PC to properly eject the disk before reconnecting it to your Macbook can also resolve the problem.
Additionally, check if the fsck process is preventing the disk from mounting when connected.
If fsck is indeed the culprit, killing the process could immediately mount the volume.


Question: is putty linux or unix?

Response: PuTTY, which has been ported to Unix and Unix-like systems, is known as pterm on these platforms.


Question: is zsh compatible with bash?

Response: Zsh's syntax is not completely compatible with bash, but it's close, so a lot of code will keep working, such as typical aliases and functions; the main differences are in interactive configuration features.


Question: what are git staged files?

Response:
Git staged files act as an unnamed, uncommented local commit, providing an intermediate step between completing work and making a permanent repository commit.
It's like a loading dock where you can decide which changes get shipped away.


Question: how to code faster (without sacrificing quality)

Response:
Employ tools that offer productivity improvements, such as ReSharper, and upgrade hardware by adding more RAM or using a solid-state drive.
Making use of code generators can also speed up the coding process, particularly when dealing with repetitive tasks, and gaining more practical experience can lead to faster and more efficient coding over time.
Staying updated with technology and studying design are additional components that can contribute toward improving coding skills.
It's advisable to use cognitive skills more effectively and minimize the amount of testing where possible.
The refinement of decision-making abilities comes from gaining experience and engaging in purposeful practice, with the aid of continuous feedback from various sources like side projects, open-source contributions, and programming exercises.


Question: google backup: multiple devices using the same account - what happens on restore?

Response: Each device maintains its own backup, as evidenced by the individual apps and data linked to specific devices that do not cross over upon factory resets.


Question: how do i transfer my ios developer profile to another computer?

Response:
From Mac OS X, you'll need to export your private key from the Key Chain where your certificates are running.
Alternatively, this can be managed directly within Xcode, which allows you to export your developer profile from the Organiser's devices tab.
For those using Xcode 5 or later, import/export functions have evolved, and your developer account should be managed through Xcode Preferences under Accounts.


Question: how do i download music from dropbox to my ipad?

Response: Unfortunately, because of the way iOS is architected, it is not possible to take music from third-party apps or websites and put them into Music.app.


Question: what is the purpose of the hash command?

Response:
The hash command is how you interact with that system; you can also use it to remember executables in non-standard locations, and use it to un-remember file paths.

It can be used to easily detect whether a command is available: CMD=gzip if hash bzip2; then CMD=$_ fi.


Question: how can i run a script on boot?

Response:
If you have root access, you can edit the script /data/init.sh that executes at boot.
For users with magisk installed, .sh files can be placed in specific magisk directories, like ` /sbin/.magisk/img/.core/service.d/` or `/sbin/.magisk/img/.core/post-fs-data.d/` and executed during boot, ensuring the script is set as executable.
However, for scripts to run properly, it is essential to ensure SELinux policies are adjusted to allow unrestricted contexts like the one Magisk uses, which is u:r:magisk:s0.


Question: what technical reasons are there to have low maximum password lengths?

Response:
Some systems impose restrictions due to incompatibilities with legacy systems that are outdated and cannot support long passwords.
There is also a general consensus that password length should not be unnecessarily limited from a security standpoint, or if they are, that the limit still allows for strong passphrases.
In terms of database storage, if passwords are stored insecurely in plaintext, then the maximum length is likely dictated by the database storage field size.
Additionally, a hashing system like bcrypt may influence the imposed limit since it only processes the first 72 characters.
Customer service considerations also play a role, with some companies aiming to minimize password recovery issues, potentially contributing to a ceiling on allowable password lengths. .
Similarly, concerns for user experience and preventing frustrations with input fields inform the decision to limit password lengths.
Other motivations might include ensuring compatibility with various interfaces, such as numerical keypads on ATMs or telephones with limited inputs, and compliance with regulations set by individuals who may lack a strong understanding of IT security.
It is also mentioned that lengthy passwords aren't necessarily a foolproof security measure, as they can still be stolen, and other security mechanisms like tracking login locations may be more effective.
User experience considerations, like keeping passwords memorable and manageable, also suggest an optimal length.
Lastly, some sites feel that brute-force protections, like limiting login attempts, render the need for longer passwords negligible, suggesting the use of random characters to increase security instead of length.


Question: set default mail client in osx without adding an email account?

Response:
RCDefaultApp is a free solution that integrates as a control panel, letting you set defaults for applications on your system.
Microsoft provides the SetDefaultMailApp tool, which is straightforward to use.
You could employ the system's Python interpreter with a specific command to change the default mail app.
Another method involves using Brew to install duti, which allows setting the default mail client via the command line.
SwiftDefaultApps is an updated replacement for RCDefaultApp and can be installed via Brew.
MSFT Mail Changer app for Mac provides an easy-to-use interface to change your default mail client without requiring installation.
Alternatively, if installing third-party apps isn't an option, adding a junk mail account can help you bypass certain limitations and access the Preference pane to make the necessary changes.


Question: disk space not freed up after deleting files and emptying trash

Response:
You can disable the local backups by running one of the following commands, depending on your version of OS X.
For older versions (pre-Leopard): sudo tmutil disablelocal.
Otherwise: sudo tmutil disable.
To address issues with mobile backups taking up space, a weekly disablement and enablement of Time Machine through its preferences has been suggested.
Sometimes deleted content could remain in the .Trashes folder, which can be removed via the Terminal command: via sudo rm -rf someFolderName.
The inability to free file space might be due to applications that hold onto the file, and skipping the backup process can resolve this.
Simply toggling Time Machine on and off has been found to fix related problems for some users.
The correct command for disabling local snapshots in High Sierra is: sudo tmutil disable localsnapshot.
If faced with incorrect disk space reports, restarting the Mac and running the Disk Utility app might immediately correct the numbers displayed in Finder.
Local snapshots, typically part of Time Machine automatic backups, may persist even when such backups are disabled, as observed on some systems.
Launching the System Information app, selecting Window > Storage Management, and observing storage can help with disk space calculations.
A complex method of adding and deleting volumes on APFS-formatted drives can update free space calculations; however, this should be a last resort and is not recommended for less technical users.
Finally, Purgeable storage or Optimized storage features in macOS can affect available free space as reported by the system.


Question: are null references really a bad thing?

Response:
Null references permit code that doesn't make sense, essentially enabling nonsensical operations on objects that are supposed to have concrete values; this situation occurs because null indicates the absence of a value.
Furthermore, the use of null is criticized as inherently "evil" since it can generate errors like NullPointerExceptions (NPEs), leading to time-consuming debugging and fixing.
It also disrupts the consistency of static typing by introducing unexpected behavior during runtime, consequently undermining the reliability of type-checking compilers.
However, some defend null pointers as tools that can be beneficial and argue that treating them as an enemy is a misinterpretation; they highlight the ease of fixing null pointer bugs compared to those involving invalid non-null pointers.
Despite the pitfalls, one must also consider the potential greater evils of not having null values at all, as the absence of data is an intrinsic part of dealing with real-world scenarios.


Question: what is the difference between an attribute and a property in c#?

Response: Property implies something possessed by something else, while Attribute suggests something that is an inherent characteristic.


Question: why and how are ethernet vlans tagged?

Response: If you have more than one VLAN on a port (a "trunk port"), you need some way to tell which packet belongs to which VLAN on the other end; a VLAN tag is used on the trunk port, where the Ethernet frames are tagged in accordance with the 802.1Q standard.


Question: linux where are acls stored?

Response:
In Linux, Access Control Lists (ACLs) are stored as metadata in the file inodes, similar to traditional permissions, dates, and so on.
The ACLs can vary in size, and as a result, they are typically stored in separate data blocks on the disk or within the file system.
Specifically, each shadow inode is responsible for storing an ACL in its data blocks.


Question: what is the difference between /opt and /usr/local?

Response:
The /opt directory is useful for quickly testing new applications without formally packaging them; they can easily be removed if the applications do not meet requirements.
On the other hand, /usr/local is meant for software not managed by the system's package manager but intended to adhere to standard Unix deployment protocols, while opt is for software that does not follow these protocols and is deployed in a monolithic fashion.
Software in /usr/local is typically built and installed locally by the system administrator, with all files under /usr considered shareable across operating system instances, though this is not common practice with most Linux distributions.
In contrast, /opt is designated for unbundled, pre-built packages provided by third-party distributors and often includes commercial software.
The prevailing setup for clusters involves default environment variables and uses shared libraries in /usr/local, whereas /opt does not follow this convention, allowing for multiple versions of software to coexist without environment conflicts but at the cost of potentially using more disk space.
Conventions play a significant role in the arrangement of UNIX/Linux file systems, with /usr/local reflecting older traditions and /opt representing newer practices; ultimately, system administrators decide the setup based on their specific needs.


Question: should i keep my github forked repositories around forever?

Response:
For managing your GitHub forked repositories, consider archiving them by tarring or gzipping and placing them in an archive directory.
If your pull request has been accepted and you haven't made any other personal changes, it's advisable to delete it.
GitHub recommends tidying up and deleting forked repositories, especially after they've been merged.
However, whether you keep or delete the fork depends on your future contributions and whether you want to maintain a clean portfolio of projects.
An issue related to the "Unknown Repository" has been resolved, so you should be okay to delete repositories once all branches have been merged.


Question: how can i verify the authenticity of an apk file i downloaded?

Response:
To verify an APK's public key, you would attempt to validate the public key within the APK, which is usually located in the META-INF/CERTS.RSA file.
A new tool called apksigner, found in the build-tools section of the Android SDK, facilitates the verification process.
Additionally, VirusTotal.com provides a free service where APKs can be uploaded to check for virus signatures.


Question: extract only a specific file from a zipped archive to a given directory

Response:
To extract a specific file from a zip archive, use the command `unzip ARCHIVE_NAME PATH_OF_FILE_INSIDE_ARCHIVE`, which will unzip the file to the current directory.
To list all files in a Zip archive: unzip -l ARCHIVE_NAME.


Question: convert .mov to .mp4

Response:
You can use Handbrake to convert .mov to .mp4 files, as well as many other formats.
VLC can also do the same: Simply open it up, select "File" then "Convert / Stream" and load the video you want to convert, then choose the format you want and "Save as File".


Question: lock screen command one-liner

Response:
To initiate a screen lock, you should set your preferences to have the screen lock when the screen saver activates, and you can use a specific terminal command to start the screen saver itself.
If you're seeking other methods, you won't find that there is a direct command line way to lock the screen, but applications like QuickLock offer alternatives such as setting keyboard shortcuts for locking the screen and typing your password unlocks it when the screen is locked.
Another option includes using BetterTouchTool to assign a keyboard shortcut to switch to the login screen or using Alfred and its universal hotkey to trigger a screen lock.
Recent macOS versions have a Lock Screen Menu item directly in the Apple menu, superseding previous methods.
For a custom approach, you could create a binary using a terminal command that exploits the keychain menu plugin to lock the screen.
Alternatively, on OS X 10.9 and later, you could use 'pmset displaysleepnow' in the terminal if your preferences are set rightly at System Preferences under Security & Privacy options.
AppleScript through 'osascript' can also be a medium to command the Finder to sleep, albeit not directly locking the screen.
There's even a way to add an alias in your 'bashrc' file that triggers the 'afk' command affecting a locked state.
On OS X Mojave, you can start the screensaver engine using this command: /System/Library/CoreServices/ScreenSaverEngine.app/Contents/MacOS/ScreenSaverEngine.
Regardless of the chosen method, ensure your system preferences are adjusted to require a password immediately after the screen saver activates.


Question: is there any technical security reason not to buy the cheapest ssl certificate you can find?

Response:
When considering the acquisition of SSL certificates, it's important to note that extended validation is unnecessary unless you require the green bar (EV SSL) feature.
Across multiple discussions, it's been pointed out that the deciding factor for domain validation certificates should be browser trustworthiness over any cryptographic advantages that one supplier may have over another.
Cost-effectiveness is emphasized as well, with recommendations to opt for the cheapest trusted option available.
A basic SSL certificate satisfies the essential criterion of domain authority validation, and for most users, any additional features may not present a tangible benefit.
The security of a website in the eyes of its users is not significantly impacted by the choice of the Certificate Authority (CA) as long as the selected CA's practices do not incur distrust among browser vendors.
Finally, opting for the least expensive technical solution that is still widely recognized by browsers is usually sufficient unless specific browser warnings, such as Comodo Dragon's treatment of DV certificates, are a concern for your user base.
More expensive SSL certificates may offer dynamic seals and a greater fraud warranty, though technically, a basic SSL certificate offers similar functional security as the most expensive ones on the market.
Let's Encrypt is highlighted as a viable option that provides certificates at no cost and is technically on par with others, although it may pose challenges for sites not accessible via the Internet.


Question: how do i delete all terminal mail?

Response:
To empty your mail file, you can execute the command: > /var/mail/$USER.
This should suffice, but to delete the mail file, requires sudo.


Question: what does the @ (at) symbol mean on osx ls?

Response: On OSX, the presence of a @ symbol signifies that the file or directory has extended attributes.


Question: what is the difference between -m conntrack --ctstate and -m state --state

Response: The state is a part of conntrack and just a simpler version of it.


Question: quickly calculate date differences

Response: For unit conversions and calculations, including calculating the difference between two dates, qalculate is a recommended tool that comes with a GTK and KDE interface.


Question: are vlans and subnets the same?

Response:
They are very much different.
A subnet specifically refers to an IP network like 192.0.2.0/28, while a VLAN pertains to the 802.1Q standard, allowing for distinct MAC address tables for each port, effectively separating them from each other.
VLANs and subnets are not interchangeable as they function at different layers of the network, with VLANs operating at the Ethernet level and subnets at the IP level.
Moreover, a VLAN is associated with Layer 2 (L2) and can contain one or more Layer 3 (L3) prefix or subnet.
Despite this, in practice, subnets and VLANs often have a correlated 1:1 mapping because both represent a single broadcast domain, which is why they tend to be overlaid in most implementations.


Question: what is the difference between print and echo in unix?

Response: When comparing "printf" and "echo," the former offers additional formatting capabilities: specifically, it doesn't automatically append a new line to the output, contrary to "echo," which does.


Question: enable install via usb without creating mi account

Response:
To bypass the MI account requirement for USB installation on Xiaomi devices, you can navigate to 'Settings > Additional Settings > Privacy' and check the 'Unknown Sources' option, and also go to 'Settings > Additional Settings > Developer Options to turn on 'USB Debugging'.
Additionally, if you prefer not to have an MI account connected to your device, you can create a temporary account, enable the 'Install via USB' option, and then log out from the MI account.
However, if your Xiaomi phone is running MIUI 8 or above, 'Install via USB' will not work unless you connect to a Chinese server, such as using a VPN service to connect to a Shanghai server, before enabling the option within developer settings.


Question: how the f*&% to stop voice-to-text from censoring profanity?

Response:
In most Android devices, you can find an option to block offensive words within the settings for voice input and output.
For example, on Android 8.1, it's under Settings, then System, followed by Languages & Input, Virtual Keyboard, Google voice typing, and finally the Block offensive words option.


Question: how do i change the name of my android device?

Response:
Changing your device's hostname requires terminal access, typically as a root user.
Development settings in the Application Settings also provide an option for 'Device hostname' which you can alter.
Alternatively, there is a Hostname Changer app available on the Google Play Store that requires root access to function.
In some modified ROMs, such as CyanogenMod, you can find the device hostname under Settings > Developer Options without the need for rooting your device.
Lastly, for rooted devices running Android 7 or older, you may use a third-party client like busybox udhcpc to communicate the desired hostname to your router.


Question: why do business analysts and project managers get higher salaries than programmers?

Response:
One reason is simply that they are higher up in the hierarchy, so their salaries should reflect this.
The basic principle of a workplace hierarchy is that management must be paid more than their subordinates.
And in software organizations, Project Managers (PMs) and Business Analysts (BAs) are on top of the hierarchy, both being critical components of the software development.
In short, BAs and PMs are abstraction layer to development, while also being the single-point-of-contact between the customers and the company's technical staff.
That is to say dealing with people is more difficult than dealing with machines.
While programming might more difficult, management also has its share of challenges and as a far as the workings of a company goes managers provide more perceived and actual monetary value than programmers.
Furthermore, managers have to constantly make decisions and take more risks than programmers, and their jobs involve having more of the company's money at stake, so it's natural that good project managers often have higher compensation than programmers.
Also, PMs have to ensure projects get completed and if a project fails, the manager bears the responsibility, not the programmers, which may remain the case if its the programmer that screwed up.
It's also the managers who will face scrutiny from the powers that be when things don't go to plan.
In this sense the pay is proportionate to career risk and responsibility.
Managers will also generally have more experience at the top, be more mature and garner more trust from business owners.
Managing also requires a very multi-faceted skill-set: people skills, leadership, ability to estimate costs and time and juggle multiple projects.
In short, programming is much easier than managing people.
Also, the skill gained in years doing programming is not valued much in current company culture.
The principle of supply and demand also applies in the sense that there are too many developers out there in comparison to the number of skilled managers.
Finally, programmers themselves don't put salary as the highest priority.


Question: what is /usr/local/bin?

Response: "/usr/local/bin" is intended for programs that a normal user may run; it's the most popular default location for executable files, particularly those that are open source.


Question: how to fully backup non-rooted devices?

Response:
For 4.0+ devices there is a solution called "adb backup" but this only works for apps that do not disallow backup.
There is an application called Simple ADB Backup which backs up your Android phone from the desktop and does not require root.
For a more complete backup scenario, it is suggested to do NANDROID backups (or adb backup + special backup solutions for sms/call-logs/contacts) plus custom ROM updates.
Android includes a built-in way to back up and restore the contents of your phone or tablet, and all you need is a computer and a device running Android 4.0 or newer.
For a dev restore, you want a Nandroid, however, a full backup depends on what you want to recover from.


Question: how can i do a change word in vim using the current paste buffer?

Response:
You can use registers to do this, and make a keybinding for the process.

You can use yw to yank your word, such as foo, then move the cursor to the word you wish to replace and use "_dw to delete it, sending the text to the register 0, the null register, (so it doesn't overwrite the contents of the " register, where yanked/cut text goes by default), using "0p (or, cw then ^R0 (which is repeatable)), and then simply paste with p.

You could write a plugin to simplify this process to achieve maximum speed; one such available is called: ReplaceWithRegister.

You usually replace strings with :%s/.../.../ and you can do this with the word under your cursor.

You could simply paste before you delete: ’yw’ then go the word you want to replace, ’pldw’ (paste, move one character right, delete word).


Question: xfce how to change resolution?

Response:
The easiest way to change the resolution is to do so via the "Display" option, which can be accessed via Application Menu > Settings.
Alternatively, you can do so in the terminal emulator using: xfce4-display-settings command.
It's also possible to change the resolution by manually modifying the file: .config/xfce4/xfconf/xfce-perchannel-xml/displays.xml.


Question: are root certificates self signed?

Response: Root certificates are inherently self-signed; they can only be self-signed, as per their definition.


Question: how to make textedit open with a blank file by default?

Response:
To make TextEdit open with a blank file by default, follow these steps: Go to System Preferences > iCloud > uncheck "Documents & Data" from the sync list.
Additionally, navigate to System Preferences > iCloud > iCloud Drive (Options) > uncheck TextEdit.


Question: what is the point of using dto (data transfer objects)?

Response:
In some cases, domain objects can be utilized as DTOs and provided directly to the display layer, particularly in simpler applications where a single unified data model is viable.
Nevertheless, for more intricate systems, it's crucial to implement a mapping from domain models to DTOs to prevent exposing the entire domain model to the client.
DTOs can encapsulate logic for API responses, promoting manageable, testable variations of responses from objects to different formats, underscoring their continued relevance, as seen in the creation of testable response formats for APIs.


Question: is there an easy way to replace duplicate files with hardlinks?

Response:
To identify and manage duplicate files on a Unix-based system, you can use 'duff -r target-folder', which allows you to rapidly find duplicates and run a specific command to produce hard links automatically to these files.
Similarly, 'SmartDupe' is an option for users on Mac or Unix systems that can replace duplicates with hard links.
If you seek a more advanced tool, 'rdfind' could be your choice as it offers functionality like deleting duplicates or replacing them with soft/hard links and supports different checksum algorithms.
`Apt show hardlink` can detect and replace multiple copies of the same file with hardlinks.
Lastly, 'jdupes' is a fast-running using the command: `jdupes -rL /foo/bar.


Question: zip everything in current directory

Response:
Install zip and use zip -r foo.zip.

An alternative to the zip format is tar: tar -czf copy.tar.gz whatever/ (where "whatever" is the folder).


Question: is there an excuse for short variable names?

Response:
One suggestion is that variables with short lifetimes should be given short names, with loop counters often being single letters like 'i', 'j', or 'k', and local variables typically being brief but descriptive names.
It appears that these variable names are based on the abbreviations you'd expect to find in a physics textbook working various optics problems, which can make the code clearer and more relatable to experts in that field.
If the original programmer finds short names easier to work with, this practice is justified.
However, caution is advised when renaming variables in legacy code: "if it's not broken, don't fix it" as it's better not to risk introducing new bugs through unnecessary changes.
Terse variable names are often justifiable for certain variables which are well-known in the problem domain, such as game development or other specific problem domains where extensive descriptions are redundant.
The general rule is that you can use short variable names in cases where you know that people who are "skilled in the art" of your particular code will immediately understand the reference of that variable name.
In fact, there absolutely can be times when a short variable name is all that is necessary.


Question: how to make `sudo` preserve $path?

Response:
You can input `sudo env "PATH=$PATH" godi_console`.
You should also be aware of the `env_reset` option within `sudo`, which can be disabled in the `/etc/sudoers` file.
Another method to run a command allowing your `PATH` to be recognized by `sudo` is to use the syntax `sudo $(which your_command)`.
Similarly, you can use `sudo "PATH=$PATH" [your command]` without altering the `$PATH` variable itself.
Lastly, the command `sudo --preserve-env=PATH env [command]` can be used to override the `secure_path` settings.


Question: what are whatsapp voice notes?

Response: Voice notes are voice recordings that you can make with Whatsapp.


Question: how to choose on which display application switcher shows?

Response:
To determine which display the Application Switcher shows on, experiment with moving your Dock to a different screen through System Preferences > Dock > Position on screen.
Additionally, you can use the cmd+tab shortcut, and the app switcher will relocate to the display where your mouse is positioned.


Question: now that it is 2015, what ssl/tls cipher suites should be used in a high security https environment?

Response:
What is the 'ideal' cipher suite completely depends on the application and target audience, but you should rely chiefly on the AEAD suites, which provide strong authentication and key exchange, forward secrecy, and encryption of at least 128 bits.

A good way to test the security of public HTTPS websites is Qualys SSL Labs.


Question: keyboard shortcut for restoring applications from the mac os x dock?

Response:
To focus on the dock using keyboard shortcuts, you can press fn+control+F3 or Ctrl+Fn+F3 depending on your keyboard preferences.
To restore a minimized application, use Cmd+Tab to switch to the app, then release Tab, but keep holding down Cmd, then press and hold Option, and release Cmd.
Alternatively, press Command+Tab until you see the app's icon, then hold the Option key before releasing the Command key to restore it.
When an application is already in focus, you can control which window to bring to the foreground: use Cmd+Tab, then the arrow keys, and press Enter to choose a specific minimized window.
You can also use Cmd-Down, follow with two downward arrow key presses and then Enter to restore minimized windows.
Some applications like iTunes and Calendar have unique shortcuts like ⌘ Cmd+⌥ Opt+1 and ⌘ Cmd+0 to bring up certain windows.
For OS X El Capitan users, after minimizing with Cmd+M, press Cmd+L to restore the window.


Question: how do i disable or get rid of the startup sound my mac makes?

Response:
To disable the startup sound on your device, you can use StartSound.PrefPane which essentially sets the volume to zero upon shutdown and then restores it again after login.
Additionally, you could simply reduce your Mac's volume to zero before restarting to avoid hearing the startup sound.
Another possibility is to input a script into Terminal that mutes the output: type: sudo -s Give the password when asked for then: cat >/private/etc/rc.shutdown.local #! /bin/sh /usr/bin/osascript -e 'set volume with output muted' then press Ctrl-D and type "exit", though you would need to manually increase the volume afterwards if you want to listen to anything.
Specifically for Snow Leopard and earlier machines, you can download and install "StartupSound.prefPane" which will install a preference pane in system settings to allow you to adjust the startup volume and disable the startup sound.
A straightforward action like holding down the mute button during startup can also achieve a quiet boot.


Question: how to install desktop environments on centos 7?

Response:
To install the GNOME Desktop Environment using YUM, input the command "# yum -y groups install 'GNOME Desktop'" directly into the terminal.
Alternatively, you can use Systemd to set up a graphical interface by installing GNOME with the command "$ sudo yum groupinstall 'GNOME Desktop'" and then creating a symbolic link to set the graphical target as default with the command "$ ln -sf /lib/systemd/system/runlevel5.target /etc/systemd/system/default.target".


Question: why dont all companies buy developers the best hardware?

Response:
The productivity difference between top-end and almost top-end machines is often negligible, while the price difference is considerably greater.
There is also no reason to overspend on such top-end machines unnecessarily.
Additional costs and productivity losses associated with constantly updating hardware, such as migration costs and loosing out on volume purchasing must be considered.
Also, the absence of dedicated IT staff may further complicate the process.
Some companies may also be highly leveraged or cash poor, leading to financial decisions that prioritize other investments over hardware upgrades.
Moreover, budget constraints can cause a discrepancy in the available funds for hardware as opposed to developers' salaries.
Furthermore, there is often a misunderstanding among employers regarding the impact of hardware on developers' work.
While work is completed, albeit at a slower rate, due to inadequate hardware, the expense is not always visible to those outside the technology department while those making the decisions might be completely unaware of any issues.
In some instances, managers do not recognize the need for high-quality tools for software developers, affecting productivity.
On the other hand, having to support special, high-end machines incurs its own costs.
Costs associated with keeping hardware current are not limited to the purchase price but also include requisition, installation, support, and disposal.
High-end machines are seen as overkill by some employers who have to juggle cash flow and other financial commitments.
Also, the best hardware doesn't necessarily produce the best developers.
Furthermore, decision-makers are not always developers, which can affect the kind of hardware purchased, emphasizing policy over personal needs resulting from risk aversion among management and poor communication among other issues.
Numerous conflicting factors influence business finance and resource allocation, and without understanding specific contributions to the bottom line, investment in better tools can be overlooked.
Additionally, improving PC hardware doesn't directly contribute to increased sales, so it might not be prioritized by finance departments.
It might also be the case that companies that don't provide sufficient hardware may consider their developers a liability rather than a resource.
Some companies are not invested in hiring top talent and are content as long as the work is done, regardless of the equipment used.
Lastly, companies may hesitate to invest in better equipment if they are under financial stress or if they don't perceive a bottleneck in software development and in large organizations, hardware choices are often dictated by fixed, centrally managed specifications aimed at minimizing support costs.


Question: is telegram secure?

Response:
Telegram seems to offer more secure communications in transit, according to their 'secret chat' feature, which suggests it could provide a higher security level for messages being transferred.
The EFF's Secure Messaging Scorecard grants a 100% security rating to "Telegram (secret chats)".
However, some experts don't consider it to be secure as its protocol, MTProto, is controversial because it was created without crypto experts, resulting in certain vulnerabilities, as highlighted by various security researchers.
Furthermore, despite any secure protocol that may exist, the app itself has suffered from significant vulnerabilities, undermining the security of communication overall.


Question: how can i get distribution name and version number in a simple shell script?

Response: To figure out your Linux distribution without the LSB release file, you can search for distribution-specific release files.  Alternatively, you can use the command: `lsb_release -a` or `cat /etc/*-release` in the terminal to get the required information.


Question: what is the difference between port channel and etherchannel?

Response:
"EtherChannel" (or "Link Aggregation") is the technology that allows you to combine several links between two devices and use them at the same time as a single interface.
The "Port-channel" is the just the name of the virtual interface in IOS.


Question: executing chdir before starting systemd service

Response: For systemd versions 227 and higher, use [Service] WorkingDirectory=/usr/local in the configuration.


Question: in centos, what is the difference between yum update and yum upgrade?

Response:
Yum upgrade will eliminate obsolete packages, while yum update may or may not do this, (some say that it will not).
The removal of obsolete packages can be risky, as it may remove packages that you use.
Because the upgrade definitely will remove obsolete packages, the update is the safer option.


Question: how to list keys added to ssh-agent with ssh-add?

Response:
Use the `-l` option with `ssh-add`.
The'- L' option will suffice if you wish to see the full key in OpenSSH format.


Question: is it normal for people to not work?

Response:
One possible reason for lackluster work attitudes could be the example set by management, which influences employee behavior.
Many individuals may be doing just enough to avoid termination, satisfied with just receiving their paycheck.
In roles where extra effort doesn't equate to additional rewards, employees may not find the incentive to push themselves harder, setting a lower standard to avoid increased expectations.
Organizational inefficiencies, such as excessive bureaucracy, can also hinder motivation by slowing workflows, contrasting with the dynamic nature of less structured environments like startups.
It's important to note that not all jobs, like software development, are marked by continuous active work; much of the time can be spent planning and problem-solving rather than coding.
If individuals appear unproductive, it could indicate underlying systemic issues.
Effectiveness in work is complex and cannot be solely judged on immediate output; factors like employee contentment play a significant role.
Moreover, developer productivity can vary based on experience and the nature of the job, with less coding but more thoughtful work expected from senior roles.
Every industry has varied work ethics, and adapting or seeking a better-suited environment is important.
Furthermore, productivity styles can differ, with some professionals interspersing bursts of intense work with periods of apparent inactivity, which may be misconstrued as laziness.
It's important to avoid quick judgments about work ethic, someone surfing might be spawning multiple background threads and thinking about the best way to tackle a problem, or someone else might seem inactive because they're waiting for their code to compile.
In making the distinction between professionals and workers: professionals often need time to think and innovate, differentiating them from more routine task-oriented workers.
Feeling unobligated to work hard can sometimes stem from a lack of engagement or appreciation by management, and there can be a strategic aspect to pacing one's work to manage expectations.
Pair programming is recommended for increasing focus and reducing distractions.
It's also worth noting that workplace culture and personal values heavily influence work habits, and finding a rewarding and challenging job can lead to a better work-life balance.
It is considered normal for some individuals to put in less effort while others work at their maximum capability.
Our culture pays people for working a 40 hour (or X hour) week rather than on a task basis, which is a terrible idea because it offers no motivation.


Question: how to get full path of original file of a soft symbolic link?

Response:
"ls, stat, readlink" are some of the commands useful for interacting with files and symbolic links on Linux systems.
Stat will give you the information you require, for example: $ stat current File: `current' -> `/home/user/releases/build/'.
You can also combine the which command with readlink, for example: readlink -f `which command`.
Or you can combine it with stat: `which command` | grep File.
Finally, To find the real path of a symbolic link, the "realpath" command can be utilized.


Question: difference between pts and tty

Response: A tty is a regular, or native, terminal device, and the backend is either hardware or kernel emulated (the console on your server, for example); a pts is a pseudo terminal slave (an xterm or an ssh connection).


Question: are software engineers really engineers?

Response:
The question of whether software engineers are truly engineers sparks varied opinions: Some argue that it's not engineering, emphasizing the absence of strict scientific requirements or the need to pass state engineering tests.
On the contrary, proponents assert that software engineering is indeed an engineering discipline.
Others lean towards a negative perspective, stating that being an engineer necessitates adherence to a cause-and-effect timeline, which may not align with the nature of software development.
Despite this, some find the term "engineering" less fitting to describe software development, indicating a divergence in views within the community.


Question: how do i view source in the android browser?

Response:
Using JavaScript's alert method is a way to return the source code of a webpage.
Additionally, one might install an app called View Web Source to view the source while browsing on a mobile device.
For capturing source code in a development environment, it's useful to install Android Developer Tools, which come with adb.
If debugging is the primary goal, installing a user agent switcher extension for Firefox or Chrome on your desktop is beneficial; this allows viewing the mobile version of a site with desktop debugging tools.
To view a source and modify it live, the Weinre remote debugger can be handy.
Chrome and Firefox on Android support viewing the page's source by simply prefixing the URL in the address bar with "view-source:".
Opera browser users can type "server:source" in the address bar to view the source code.
Chrome has a remote debugging facility that enables viewing Javascript-modified sources on a PC when a phone is connected via USB.
If an app hasn't been updated, trying VT View Source is an alternative.
Creating a new bookmark (bookmarklet) named "View Source" on Mobile Chrome can simplify the process of viewing a page's source code.


Question: how to find cause of high kernel_task cpu usage?

Response:
This is likely a hardware problem caused by lack of cooling: you might have a broken fan, lots of dust or a high chassis temperature caused by charging.
Running spindump and or sample process from the activity monitor may help provide you with more information about what’s going on.
Sometimes the CPU usage drops if you use a different port for charging a laptop.
On a MacBook Pro, use the sockets on the right instead of the left.


Question: why do sites implement locking after three failed password attempts?

Response:
The lockouts are intended to prevent a brute-force attack, and also provide protection against password guessing by human attackers, especially by individuals who already know of a portion of the password, for example, by looking over someone’s shoulder, plus you can use it to trigger a warning that an attack is happening.

Companies that are public (sell shares in stock exchanges) are regulated under Sarbanes-Oxley Act, which requires critical software applications to comply with certain security features, one being to lock accounts after failed password attempts.

However, some suggest conducting a business-focused risk-analysis trade-off: figure out how many failed, legitimate attempts are likely, then double it.


Question: what are the real life implications for an apache 2 license?

Response:
Your project appears to be subject to the '4 Redistribution' clause of a certain license, which mandates that the text of the Apache 2 license must be included in the project's documentation for derivative works.
You can modify the software as you desire for software under the Apache License Version 2.0.
Yet, it is crucial to closely examine section 4(b) of the APLv2 to understand your obligations concerning the NOTICES file and how to display its contents properly as part of your modified work.


Question: why does numbers hide a huge png file in exported excel sheets?

Response: Numbers hides a huge PNG file in exported Excel sheets as the default shape fill, which is strictly unnecessary if there are no shapes.


Question: do i need csrf protection?

Response:
If a GET request is involved in altering the application's state, which ideally it should not be, then implementing CSRF protection becomes crucial.
Specifically, CSRF protection is deemed necessary for state-changing operations within an application.
However, if the GET request is primarily focused on returning data, CSRF protection may not be required.
Ordinarily, safe methods do not have to be protected against CSRF and if your site is implemented as per standards, your GET requests should be safe.


Question: how does duckduckgo know my native language even though i am using a vpn in a country with a different language?

Response: One possible explanation is that DuckDuckGo is using the headers that are sent in your request to determine their display, for example, your system could be using IPv6 data, which will reveal your home IP as usual.


Question: how to kill a runaway cat?

Response:
On the Linux virtual console just switch to another one ((Ctrl +)Alt + Fx); or try Ctrl-C, you can also try sending SIGQUIT with Ctrl-\..

The following command is for this: tmux option c0-change-interval and c0-change-trigger.


Question: why zsh ends a line with a highlighted percent symbol?

Response:
This happens because it is a "partial line," and by default, ZSH goes to the next line to avoid covering it with the prompt.
Also, It's a specific feature of ZSH (and now fish as well) designed to make unterminated lines in a command's output visible.


Question: /usr/bin vs /usr/local/bin on linux

Response:
Most software packages provided by the distribution usually land in /usr/bin/.
However, when it comes to system-specific and manually installed scripts, you would place them in /usr/local/bin/.
In terms of hierarchy, /usr/bin/ is the primary directory for executables that are required by normal users and not necessary for booting the system or system restoration.
On the other hand, /usr/local/bin/ is reserved for binaries and non-binaries specific to the local system.
These distinctions maintain order across different system directories and align with the filesystem hierarchy standards.


Question: xfce how to switch workspace?

Response:
The Xfce 4.12 interface features default shortcuts such as Ctrl+Alt+1, Ctrl+Alt+2, and so on, to move windows to specific numbered workspaces.
Xfce 4.12 also has various shortcuts dedicated to maneuvering windows between different workspaces, although there are no default shortcuts for moving workspaces in directions such as left, right, upper, or bottom.


Question: does using == in javascript ever make sense?

Response:
Yes, using `==` in JavaScript can make sense and is convenient in certain situations including when comparing a key with a numerical value.
Additionally, if you need to compare padded numbers, such as comparing "01" to normal integers, the `==` operator works just fine.


Question: how to turnoff screen / lock macbook pro with touch bar using keyboard?

Response:
The sleep function can be added to the Touch Bar on MacBooks by accessing the system preferences, selecting the keyboard option, and then customizing the control strip and then dragging the sleep icon to the Touch Bar.
Another method to secure your screen quickly is to use the command 'Activate Lock Screen' with the keystrokes control⌘Q.
Alternatively, from the terminal, the command 'pmset displaysleepnow' can be used to put the display to sleep immediately.
Additionally, you can install BetterTouchTool and set up a specific keyboard shortcut, such as 'Ctrl + Shift + Del', to simultaneously turn off the screen and lock the computer.


Question: what is a good analogy to explain to a layman why passwords should be hashed?

Response:
Hashing can be understood as a method of writing text so that it cannot be read by others, which is crucial for protecting sensitive information like bank pins.
The necessity of using hashing for passwords is compared to avoiding a $5 million lawsuit; it is a financially sound defensive measure for companies.
A password hash functions like an unbreakable code, providing security because it is one-way and cannot be reversed to reveal the original password.
An unhashed password is likened to a transparent lock that can be easily bypassed if observed correctly.
Hashing is described as a home guard, a last line of defense for password protection, given the severe consequences of not having this security in place.
Finally, the analogy of password hashing without salting is equated to a shared bank vault that must be cracked, while salting each hash equates to having private bank vaults for added security.


Question: when is it appropriate to not unit test?

Response: JUnit's philosophy suggests that if a piece of code is too simple, it should not be subjected to testing.


Question: how much business logic should the database implement?

Response:
One opinion advises finding a middle ground from their experience in seeing projects in which programmers have left vital elements or where most of the business logic was implemented in database code.
Another opinion recommends keeping business logic out of the database as much as possible to avoid issues like decentralization and encapsulation problems.
Additionally, business logic doesn't belong in the database in the case of multi-tier applications.
On the other hand, if your business logic involves set operations, most likely a good place for it is in the database since database systems are efficient at performing set operations.
If the business logic involves some sort of calculation, it probably belongs outside of the database/store procedure since databases are not designed for looping and calculating.
One person's experience from working at companies with different perspectives is that it is best to use Stored Procedures when execution time is important in terms of performance.
Place logical constraints or ubiquitous expressions, or single statements, in the database, while procedural elements, loops, and conditional branches should be coded outside the database.
Another opinion points out that it depends on what the database is used for.
Finally, there's no general answer, as it also greatly depends on a business and their culture and legacy.


Question: timezone setting in linux

Response:
The "tzselect" command is designed to assist with the task you are trying to accomplish.
To set the timezone in Ubuntu, you merely need to substitute 'Asia/Tokyo' with your preferred timezone.


Question: how to add a line break in a cell in excel for mac

Response:
In Excel for Mac, Control+Option+Enter, Control+Command+Enter or Control+Option ⌥+Enter can be used to create a line break in a cell.
Alternatively, you can use Alt+Enter.


Question: does craftsmanship pay off?

Response:
In most cases, craftsmanship in software development is acknowledged during the maintenance phase rather than when launching a new product.
Craftsmanship's value becomes more evident over time as organizations mature and realize the importance of well-constructed software for reducing maintenance expenses; writing well-commented and modular code does pay off.
However, truly appreciating the value of craftsmanship might require starting your own company, as it's often in employed positions where the effort goes unrecognized or is only valued much later.
In some unfortunate cases, a commitment to craftsmanship might not align with a team's culture or might even be met with resistance; this can be true in big organizations because corporate culture doesn't really encourage it.
Additionally, a focus on "best practices" could be misconstrued as over-engineering, leading to neglect of the commercial aspect of development work.
And sometimes, craftsmanship does pay off for those in leadership positions or those directly responsible for the code base, but for those facing tight deadlines, the immediate benefits might not be obvious.


Question: what is this symbol? ⎋ (it is listed as menu shortcut)

Response: The symbol you're inquiring about, represented by a circle with an arrow escaping from it, is denoted as ⎋, and it signifies the Escape key on the upper left side of your keyboard.


Question: changing the default size of iterm2 when it opens

Response:
To configure iTerm2 to open with a specific layout, first set it up the way you'd like to see it when it opens.
Then, save this window arrangement through the Window menu and set it as the default configuration in Preferences.
You can adjust the settings any time by placing things as you like them and re-saving the default arrangement.


Question: can you add blank space to a photo in mac preview?

Response:
Performing this task in preview mode is not possible.
Acorn and Pixelmator can be used for this purpose, but they both cost.
Pixelmator comes highly recommended if you seek a comprehensive photo editing tool.
Alternatively, a simpler method is to have the text in a window just above or below the picture and take a screenshot of the picture+words, if image quality is not a priority.


Question: how does shutterstock keep getting my latest debit card number?

Response:
Account Updater is a service where, when card issuers like Visa issue newly updated cards, they provide the new card numbers and expiry dates to the service.
Merchants who participate can query their stored credentials to receive updated card information from the Account Updater service.
Shutterstock, as a participant, gets updated card details when a customer's card expires or is replaced.


Question: why are ipv4 addresses running out?

Response: There are 4 billion addresses available under IPv4, which should be enough for everybody in principle, but the minority who can afford it have 15-20 devices connected to the internet, which is more down to marketing than necessity, so it comes down to money; plus, providers want to promote IPv6, and so have given out addresses like candy, until almost none are left.


Question: list all devices connected, lsblk for mac os x

Response:
To list all disks, including unmounted ones, along with their identifiers on a Mac, you can use the command 'diskutil list' in the Terminal.
If you are running High Sierra 10.13.6 or newer, the system profiler can be used to view all mounted SATA devices and the UUID of each mounted disk.
To list all USB devices and all PCI devices connected to your Mac, commands like 'system_profiler SPUSBDataType' and 'system_profiler SPPCIDataType' respectively can be run in the Terminal app.


Question: what is nproc and nofile in linux?

Response: In terms of system limitations, the nofile parameter specifies the maximum number of open file descriptors, and the nproc parameter sets the maximum number of processes allowed.


Question: right-click, create a new text file. how?

Response:
You could assign a shortcut to a script.
The cleanest way is to use a Automator script available on Github.
There is a little-known feature of the Finder called Stationary Pad which will also work.
New File Applescript with Toolbar Icon will add a new file widget to the Finder toolbar.
Or try using XtraFinder plugin for Mac OS's built-in Finder.
Alternatively, if you download and install BetterTouchTool, you can set up this action easily.
New File Menu.app can be configured to provide an experience familiar to Windows users.
Remember that if you upgraded to macOS Sierra, you may need to reinstall New File Menu (try the free version).
Using this, you can right click in any Finder window to create a new file.
If you use Alfred, you can try a workflow available on packal.org.
In High Sierra: go to System Prefs/Keyboard/Shortcuts, choose SERVICES and check "Open Selection in a TextEdit window".


Question: el capitan, expand desktop thumbnails by default in mission control

Response: To automatically expand the desktop thumbnails, setting up a hot corner to the top left is effective, as it expands them upon entering Mission Control.


Question: how many devices can you connect to iphone hotspot?

Response: The number of devices that can join your Personal Hotspot at one time depends on your carrier and iPhone model, but the typical limit is usually between 3 and 5 devices.


Question: new team lead - how to deal with a resentful former peer

Response:
When managing a team, especially as a newly assigned leader, one should avoid non-professional behavior and casual discussions that could diminish perceived authority.
In establishing leadership early in a project, clear and direct orders must be given to avoid any ambiguity about direction or intent, ensuring compliance or providing a clear case of insubordination if necessary.
Be professional and very transparent; don't try to be friends with anybody on the team and act as if you are on a mission the entire time and do not show favoritism.
Protect yourself, and document everything.
Don't invoke your authority if you don't want a fight, find out what people want, and use that to help them take appropriate action.
Maintaining a sense of humor and taking control of the situation, rather than being controlled by difficult individuals, is also recommended.
As a leader, setting clear and unambiguous parameters is vital; this involves establishing boundaries and expectations from the outset and being consistent, firm-but-fair and transparent in enforcing them.
Treating all team members equally, including unruly ones, addressing conflicts in private meetings and assuming success and fairness, treating each team member equally without preconceived judgments can be an effective strategy.
If deciding to incorporate a difficult individual into the team's success plan, understanding what motivates him, and giving tasks suited to his skills and keeping him busy is crucial.
On the other hand, isolating a problematic individual by assigning critical project parts to the core team or by taing them aisde for a private face-to-face meeting can preserve team harmony,  lessen their impact while still emphasizing the importance of their contributions.
Being straightforward with the troublesome team member  and actually tell him what others have said behind his back  while still being professional is another approach.
Establishing boundaries and expectations and managing the problematic individual with a 'short leash' approach can ensure a clear understanding of acceptable behavior, and under no circumstances tolerate insubordination.  Keeping a watch on problematic code submissions helps in monitoring potential sabotage.
Understanding the motivations of challenging individuals, meeting with his peers and former managers, and talking to him personally and privately can lead to better outcomes.
Similarly, considering the person, their state of mind, and their needs before taking any actions is paramount, as is encouraging their successes and recognizing accomplishments to foster a positive work environment.
Changing one's attitude towards challenging individuals, leveraging their strengths, and treating them with respect are strategies that can influence team dynamics positively.
Lastly, seeking guidance from upper management or a project manager can also be beneficial in handling problematic situations.


Question: how to force ssh client to use only password auth?

Response:
Use the command `ssh -o PreferredAuthentications=password -o PubkeyAuthentication=no example.com`.
It's imperative to ensure that password authentication is not prohibited in the client configuration.
When configuring SSH client settings, you can also specify options on a per-host basis in your configuration file located in the .ssh directory.
In certain scenarios, like when encountering issues with SSH servers that are not securely maintained, specifying a non-existent identity file, such as `ssh -i /dev/null host`, can be an effective workaround.
Furthermore, verifying that `BatchMode=yes` is not enabled in your `.ssh/config` is critical, as this setting would prevent the interactive password prompt from appearing.


Question: when are getters and setters justified

Response:
In Java, methods are used in interfaces rather than fields because only methods can be defined within an interface.
If there's a need to pass a field through an interface, implementing 'getter' and 'setter' methods is necessary.


Question: can i connect my kindle fire to my iphone hotspot?

Response:
The chances are more "off" than "on", as tethering isn't allowed for the iPhone or iPad (although it may be possible with jailbreaking).

Although devices such as laptops (e.g., Sony VAIO FWIW) connects well over the WiFi hotspot of the iPhone and can access the internet, anecdotally Kindle won't allow tethered connections to iPhone 4, nor will Kindle WiFi6 connect.

However, it is reported that a Kindle Fire (which is WiFi only) can connect to a mobile hotspot created by an iPhone to connect to the Internet; and that after enabling data roaming a kindle keyboard does connect via personal hotspot to an iPhone 4S.


Question: how do i kill all screens?

Response:
To terminate screen sessions you can use "screen -S $scr -X kill"; for OSX, the "pkill screen," "killall screen" or commands can be used.
When dealing with dead screens, the command "screen -wipe" may be effective.


Question: why cant i just let customers connect directly to my database?

Response:
The complexity of a database API and its potential for privilege escalation flaws present a significant security concern when considering direct access.
It's essential to manage the risk of sensitive or customer-specific data leaking into data warehouses used for giving customers indirect access.
Granting direct SQL access brings risks such as performance degradation by unoptimized queries from users, validation issues leading to data integrity compromises, and difficulties in maintaining the database when significant changes or maintenance are required.
Human error in granting incorrect authorizations can have severe consequences, challenging customers to understand the database schema and form a dependency on the database's structure.
Exposing a DBMS to the public network is advised against because it has more potential for buffer overruns, presents a large attack surface for cyber attackers, and may lead to complex and performance-impeding security auditing processes.
DBMS servers have more potential for exploits compared to web servers; thus, security experts discourage exposing DBMS to the public network.
Whether direct database access should be provided depends on the nature of the customers, with a distinction being made between public and trusted business partners.
The lack of granular access control in database engines, which typically operate on a table-wide permission basis rather than per-record, is a key concern and one of the main reasons behind advocating for an API intermediary for security and additional business function purposes.


Question: is it unusual for a small company (15 developers) not to use managed source/version control?

Response:
Working without source control is not standard practice for any size of programming team, and for a professional team, it's considered inexcusable not to use such version control systems.
This consensus is reflected across multiple sources, indicating that not using source control is by no means normal.
A variety of reasons for implementing source control are mentioned, including the organization and management of changes, branching, and automated merging capabilities that version control offers.
Additionally, it is highlighted that source control allows for precise tracking of changes, who made them, and when, alongside the ability to maintain different project versions and work cohesively on the same files.


Question: reason for both a mac and an ip address

Response:
The IP address and MAC address serve different (but crucial) purposes, so even if your computer has an IP address, it still needs a MAC address to find other machines on the same network: the MAC address gets a frame from one Network Interface Card (NIC) to the next; the IP address gets a packet from one Computer to the Server.

A Mac address is the physical or virtual address of your NIC card or network interface (from a computer on a network's standpoint, it is the physical address of that computer's NIC card), and is used to bring information to that computer on Layer 2 of the OSI model, while the IP address is required on layer 3 to communicate with computers on different subnets and devices (the IP address verifies "where" the device is located within a network).

It is easy to group TCP/IP addresses, but it is necessary to translate the TCP/IP address to the MAC address.


Question: how do you check if a port is blocked on linux?

Response:
To see if the service is on and is listening to the IP address or not, you can use: netstat -tuplen | grep 25.
To see if there is any rule set by your firewall, use: iptables -nL | grep <port number>/.


Question: understanding of diff output

Response:
Given a diff file1 file2, < means the line is missing in file2 and >means the line is missing in file1.

The normal output format consists of one or more hunks of differences; each hunk shows one area where the files differ.

In your first diff output (so called "normal diff") the meaning is as follows: < - denotes lines in file1.txt; > - denotes lines in file2.txt; 3d2 and 5a5 denote line numbers affected and which actions were performed.

The meanings of the command line switches are as follows: -r means recursive; -u shows line number; -p(small) shows the differences in C functions; -P(capital), in the case of multiple files, shows the full path.

The diff command is easier to understand if you consider that, essentially, it outputs a set of instructions for how to change one file to make it identical to the second file; each of the following cases are explained well: a for add, c for change, d for delete.

d stands for delete, but 'remove' is more clearly what happens; a stands for add, but 'insert' is more clearly what happens; c stands for change, but 'remove + insert' is more clearly what happens.


Question: my iphone keeps switching on and off charge whilst charging, how do i fix it?

Response:
There may be several contributing factors for charging issues, such as software processes; force quitting the 'usbd' process in Activity Monitor or via terminal commands has been found effective in some cases.
Alternatively, besides software issues, it could be a buildup of lint or debris in the phone's charger port, which can be carefully cleaned using a plastic or wood toothpick to gently remove the obstruction.
It's also worth mentioning that problems might arise from a damaged cable, software needing updates, or due to incompatible device communication that could be resolved by connecting through a USB hub or booting a Mac into Windows.


Question: how do i stop the adobe creative cloud app from auto-launching on login?

Response:
To turn off everything Adobe launches at startup on the Mac you need to both disable its launched jobs and the Adobe Core Sync extension.
If you run launchctl unload -w /Library/LaunchAgents/com.adobe.AdobeCreativeCloud.plist that will disable it for your user.
You can also select “Preferences” and uncheck “Launch at login” in the menu bar.


Question: whats the recommended way of copying changes with vimdiff?

Response:
Use: do (diff obtain) and dp (diff put).

However, do and dp don't work in visual mode, so when selecting lines of text in visual mode, you must use the normal commands: '<,'>diffget and :'<,'>diffput.


Question: change the mouse wheel scrolling acceleration

Response:
For enhanced experience and customization with computer mice, it is highly recommended to consider using third-party mouse managers such as SteerMouse, USB Overdrive, or ControllerMate.
Specifically, USB Overdrive allows for altering the default behavior and offers various scrolling and tracking options.
If using a Logitech mouse, one could download the Logitech Control Center for Macintosh® OS X to make adjustments to the mouse's functionality.
Additionally, a free program called DiscreteScroll can set the mouse wheel to scroll in fixed increments, such as three lines per tick.


Question: how do i hide the spotlight icon on yosemite, but keep the spotlight functionality?

Response:
The utility app Bartender can help reorganize menu bar icons by keeping them in the bar, relocating them to the bar, or hiding them completely.
Alternatively, icons can be made invisible by patching the status bar size to zero, which requires modifying the Spotlight binary and using Terminal commands.
There's also Vanilla, a minimalist app for hiding menu bar icons, as well as Dozer, a completely free app serving the same purpose.
In macOS Big Sur, unchecking 'Show in Menu Bar' in System Preferences under Dock & Menu Bar settings removes the Spotlight icon.


Question: is html a subset of xml?

Response: XHTML is a subset of XML, while HTML and XHTML are both subsets only of SGML.


Question: how can i make ctrl+right/left arrow stop changing desktops in lion?

Response: Updating an app called Karabiner can result in Mission Control shortcuts being disabled.


Question: what is the modern way to do port-forwarding on el capitan? (forward port 80 to 8080)

Response: In El Capitan, the contemporary method for port forwarding is accomplished using pf.


Question: shortcut for toggling between different windows of same app?

Response:
Use Cmd ⌘Tab as usual and on the icon of the application you want to switch windows in, press the down arrow key, then use left/right keys to navigate to the desired window across spaces and desktops.
The command could be different on different keyboards: Command+`; option+cmd+à; (Turkish) cmd ⌘ + < + control; Command+± (the one above tab); (Spanish) Cmd+^`[; next window: Command ⌘ ` and previous window: Command ⌘ Shift ` `.
For CSA language with French (Canadian) Keyboard, use Cmd ⌘ + ù Cmd ⌘ + Shift ⇧ + ù to go the other way.
For Canadian French - CSA language with US English Keyboard Cmd ⌘ + ` Cmd ⌘ + Shift ⇧ + ` to go the other way.
You can also press ctrlleft or right on your keypad.


Question: why shouldnt we roll our own?

Response:
Rolling your own or creating a secure encryption algorithm can be a difficult and risky endeavor if you are not a security or cryptography expert, as you may inadvertently introduce major security vulnerabilities.
It is generally not advisable to gamble on encryption, especially when the stakes are high and the payoff does not justify the potential risks involved.
Crafting an encryption system that no one can decrypt is a particularly challenging task even after having significant expertise and years of analysis by the cryptographic community.
However, it's essential to understand that no one can foresee all potential attacks, making solitary attempts at creating secure cryptographic systems impractical.
It's generally advised to rely on publicly vetted and expert-reviewed encryption methods rather than attempting to design your own encryption, which is an error-prone process that experts avoid.
Moreover, the process becomes even more challenging when designing systems robust against attackers with insider knowledge.
Despite these challenges, experimenting with your own cryptography can be a valuable learning experience, provided the resulting code is not used in real applications.


Question: what is tabnabbing?

Response:
Tabnabbing is an attack method where the appearance of a webpage is altered when it's not the active tab, enticing users to provide their login information upon their return.
It involves deceptive changes such as switching the favicon and title to imitate sites like Gmail, misleading users into believing they are on a legitimate page.
Additionally, it is recognized as a social engineering attack utilized via web browsers, where the attack is initialized by prompting users to visit a dangerous website which remains dormant until the user navigates away and returns to the tab.


Question: where to store a server side encryption key?

Response:
Using an external Hardware Security Module is a method to enhance security operations by offloading them to a more secure device, which is a significant step for high-stakes situations.
Encryption keys can also be bound to the admin login, providing control over encryption and decryption processes, but requiring the admin to be logged in for these actions.
Another method is to store the encryption key in memory, thus securing it against offline attacks.
When using a password to tie a service account, a Powershell cmdlet can be utilized for less script modification, making the password dependent on a further compromise of Active Directory.
To meet certain compliance requirements, a key stored in plain text on an externally encrypted and access-restricted server may be deemed sufficient.
Employing key management solutions can help manage and protect master keys, with the recommendation that these solutions should support high availability corresponding to the infrastructure.
Segmenting the key and storing each part on separate USB flash drives to be combined upon system startup is another proposed security mechanism.


Question: how do i find out the applescript commands available for a particular app?

Response:
You can start the Script Editor app, formerly AppleScript Editor, and open the app dictionary you're interested in to browse its AppleScript commands.
Alternatively, you can drag the application icon onto the Script Editor icon to access its dictionary if available.


Question: what is java programmed in?

Response: The very first Java compiler developed by Sun Microsystems was written in C, but now the class libraries are always written in Java.


Question: how to increase keyboard key repeat rate on os x?

Response:
In the Karabiner app, on the second tab, named Key Repeat, there is an option called Repeat Rate.
Modifying this setting will have an immediate impact on the keyboard repeat rate.


Question: why isnt udp with reliability (implemented at application layer) a substitute of tcp?

Response:
Both protocols are designed with certain guarantees and raw TCP has more guarantees than raw UDP.
UDP with reliability can indeed be a substitute for TCP.
However, in general, TCP is pretty optimal so it's not worth going to all the extra work and adding a (large) chance of adding bugs and security flaws.


Question: how to make right click using only keyboard on a mac?

Response:
First, you can turn on Mouse Keys through System Preferences by navigating to Universal Access and selecting the Mouse tab.
Another option is to access built-in features via System Preferences, specifically Keyboard shortcuts.
Additionally, you can go to System Preferences > Accessibility, find Mouse & Trackpad, and enable "Mouse Keys".
Another method involves pressing Option-Command-F5 and selecting "Enable Mouse Keys" from the pop-up window.
For a more customized solution, you can use Automator and Python, although this might have a slight delay.
Alternatively, there are third-party solutions such as the RightClick Alfred workflow, that provide the desired functionality.


Question: difference between a socket and a port

Response:
A socket is simply one way of sending and receiving data on a specific port.
In a more illustrative way, if we think of a machine as an apartment building, a port is analogous to the apartment number, while a socket resembles the door to an apartment.
Moreover, a port is for routing to the correct socket on the host.


Question: is it bad practice to use <?= tag in php?

Response:
It's recommended to avoid short form tags in PHP due to portability concerns.
The PHP Documentation states that as of version 5.4.0, short echo tags are always enabled, regardless of the short_open_tag setting, which makes them safe for use.
However, from PHP 7.4, the older short open tags are deprecated, with plans to remove them entirely in PHP 8, but short echo tags remain unaffected, and their use is not discouraged.


Question: where are the apk files from google play?

Response:
In older Android OS versions, apk files are usually stored in either '/cache/download' or '/data/local'.
Nowadays, however, the temporary location of the files is set by the Download Provider service, which is usually '/data/data/com.android.providers.downloads/cache'.
However, this can vary between Android versions and manufaturers.


Question: how does an event listener work?

Response:
An event listener akin to an e-mail newsletter subscription.
A succinct answer is the application receives a signal, or event, and the routine is only called at that point.
An event listener does not check if the button is pushed at all,  instead, it gets called when the button is pushed.
The event listener looks out for event firings.
There are two main strategies to check if an event happened: the pull and push.
The pull approach, also called polling, is simpler and can be implemented it without any special feature, while the push approach is generally more efficient since your code only runs when it has something to do.
Most event loops are built above some polling multiplexing primitive provided by the operating system.
In a purely polling based system, subsystem that might want to know when some particular action happens will need to run some code any time that action might happen.


Question: how could i make the results of a yes/no vote inaccessible unless its unanimous in the affirmative, without a trusted third party?

Response:
This is basically an AND relationship between the inputs and could be implemented in several ways, applying the principle of idempotency: you want a system that only produces a result (binary 1) if all the inputs are active, that is, if everybody votes yes to leave the cult, the result is leave, otherwise the system must not return any kind of information (binary 0).

It could be easily done with switches in series with a light, to be pressed (or not) secretly, at the same time, perhaps with hands covered by cardboard boxes, with the result that the light only comes on if everyone presses.

Variations on the switch method are to use layers of encryption, such as in the dining cryptographers problem, where each family member has a key to only one of the layers, or a chemical solution using a pH indicator, that will change color to indicate no if any voter chooses the liquid with the stay pH, rather than water (pH 7).


Question: are wifi passwords saved on icloud?

Response: Although it is not explicitly mentioned if passwords are stored in the backup, iCloud Backups of iOS devices include the Keychain of all saved passwords on the device, including WiFi network passwords.


Question: why cant devices on different vlans, but on the same subnet, communicate?

Response:
You have two hosts on two distinct L2 networks without anything to allow them to communicate.
There will be no ARP reply; the next thing that happens will be a timeout on A, followed by subsequent repeat ARP requests, until the application gives up.


Question: keyboard shortcut to unhide or unminimize a window in os x

Response:
To reopen an application and bring up a minimized window, press Command (⌘) and Tab (⇥), then hold the Option (⌥) key before releasing Command (⌘).
Another way to handle windows is by using Command (⌘) and H, which hides the window instead of minimizing it, allowing for an easy switch back to it without special actions.
If you want to un-minimize a specific window or all windows of an application, use Command (⌘) and Tab (⇥) to switch to the app, hold down Command (⌘), and then tap Down Arrow or 1 to enter App Exposé.
Then, you can select any window with the arrow keys and press Option (⌥) and Return (↩) to un-minimize all windows or just the Return (↩) key for a specific one.


Question: how to avoid being asked passphrase each time i push to bitbucket

Response:
You should utilize an SSH agent to manage Secure Shell (SSH) keys and connections.
Keychain is a tool that can assist with managing SSH keys and is available through package managers like apt-get in Debian and Ubuntu systems.
For an optimal setup, you should create or edit the "~/.ssh/config file: Host * UseKeychain yes AddKeysToAgent yes IdentityFile ~/.ssh/id_rsa" file to include directives that enable the use of Keychain, instruct the SSH agent to add keys, and identify the default identity file.


Question: is there the dark mode (inverted colors) in the preview application for pdf reading?

Response:
Preview currently lacks a dark mode, but for better nighttime screen interaction, you can use flux software to adjust color warmth and reduce brightness.
Alternatively, iBooks is an option that does offer a dark mode.
If you need to invert colors in Preview, the system-wide shortcut Command-Option-Control-8 enables the inversion of screen colors.
For Mac users, the Negative app provides two negative modes for PDF reading, including color inversion with sepia, and system preferences allow for the inversion of display colors as well.
Users of Adobe PDF Reader can customize settings for a black page background and dark grey document text.
A browser extension like Midnight Lizard can change colors in PDF documents opened in Chrome-based browsers, and imagemagick can be employed on a Mac to invert colors in a PDF document.
PDF Expert offers an effective dark mode for reading PDFs and performs smoothly without inverting colors inaccurately, as system-wide inversion might.


Question: how can i do development on my android device?

Response:
For Android development, you might consider trying Ruboto IRB, available on GitHub, which allows interactive Ruby scripting and is beneficial for learning and prototyping.
Terminal IDE is another option, providing a full Java / HTML / Android development environment directly on Android devices.
If you're interested in C#, there's an app called C# To Go that offers a basic C# REPL for experimentation.
For various scripting languages like Python, Perl, and JavaScript, SL4a (Scripting Layer For Android) is a noteworthy tool that grants access to Android API and can be integrated with other editors for enhanced functionality.
Within the realm of browsers, Aloha Editor is acknowledged for operating in browser environments, with Firefox mobile highlighted for its advanced HTML5 capabilities.
AIDE is an inclusive application that supports a complete edit-compile-run cycle for Android app development without requiring root access and is compatible with Eclipse project formats.
For web server solutions with PHP support, PAW Server for Android is recommended, facilitating web server functions including PHP through a plugin.
Lastly, the Android Web Developer app is specialized for web development featuring support for web languages and offering various project access methods along with code editing and previewing features.


Question: is using dot and at in email addresses in public text still useful?

Response: Yes, it might still have an impact, though it has probably never been very useful as email harvesters have probably long been scanning for that obfuscation; it is better to use some fancy advanced munger, or simply use images.


Question: is arp layer 2 or 3?

Response:
ARP is layer 2, due to the fact that a broadcast is sent on layer 2 and ARP will normally not traverse to layer 3.
However, it can provide extra features to the layer 3 protocol.


Question: can someone take down wi-fi signal?

Response:
Some devices can "jam" Wi-Fi signals, and Wi-Fi can operate on various channels.
It's possible to disrupt the communication between a router and devices by interrupting their specific frequency.
You can disrupt a Wi-Fi network without knowing the password by doing physical layer attacks i.e., jamming the frequency with your own signal.
MAC and Network Layer attacks are particularly effective against networks that use outdated security protocols like WEP, as it's easier to forge de-authentication packets and throw out stations from the Wi-Fi network.
The "Duration attack" is a type of cyber attack in which the attacker sets the duration field in frames to the maximum value and uses a low data rate, thus, this forces the access point and other clients to honor the attacker's transmission time and causes a significant impact on the network.


Question: how does learning assembly aid in programming?

Response:
Learning assembly language can enhance your understanding of core concepts in computing, such as memory allocation, parameter passing, and architecture.
It reveals the costs associated with function calls, and the handling of recursive functions and demonstrates why high-level constructs are designed the way they are.
The pursuit of such knowledge, however, should be driven by necessity or curiosity.
Before delving into assembly, a solid grasp of C or C++ is recommended due to their relevance in practical applications.
While detailed knowledge of the hardware level is not mandatory, an appreciation for the complexity and impact of your code is beneficial.
Conversely, if knowing assembly does not directly contribute to your area of work, focusing on more pertinent skills, such as software design and problem-solving, might be more advantageous.
For developers working with high-abstraction languages, understanding the next level down can aid in debugging and writing efficient code.
Finally, in some special cases, learning basic assembly could provide a foundational understanding that simplifies higher-level programming concepts.


Question: can i download google music to my ipod?

Response: After installing the Google Play Music app on your iPod, you should be able to sign in with your Google-ID, download the songs you own, and play them.


Question: is java slower than c++?

Response:
You can't measure the speed of a language, only the speed of some particular implementation.
That said, on average, code written in Java will run slower than (roughly) equivalent code written in C++.
While Java may be up to three times slower, it is often almost as fast as C++.
So, the runtime is similar in C++ and Java code.


Question: why is freebsd deprecating gcc in favor of clang/llvm?

Response:
One opinion offers that Clang/LLVM uses fewer resources than GCC and is quicker.
Another opinion advises that GCC's produced binaries are not bound by any license, thus allowing them to be used under any license that a developer chooses.


Question: when to choose fiber instead of twisted pair (copper)

Response:
Copper has a shorter max distances per link than fiber, and is susceptible to electromagnetic interference; copper also has the disadvantage that when running data cabling between different electrical bonding zones (e.g., buildings with different electrical earths), different ground potentials might try to equalize over the copper cable.

If you are going to run FCoE over the medium, then it is better to run fiber than copper as the BER for copper is significantly higher and most of the time will be outside of the tolerance for the “lossless” nature of FCoE.

Fiber beats copper as soon as distance becomes a factor, allowing for much longer max cable length distances, depending on the specification and throughput, and does not suffer from electromagnetic interference, so is particularly suitable for high electrical noise environments, and is recommended for backbone cabling where the long haul is needed; fiber also allows for wavelength division multiplexing (WDM), which you can't use with copper.

Fiber is even recommended for a short run between two cabs in a DC between core routers.

Another factor is that people are more afraid to touch a fiber cable compared to copper, so you'll get less of the "Oops, I didn't realize that was the switch uplink".


Question: how to monitor only the last n lines of a log file?

Response:
You can use watch: $ watch tail -n 15 mylogfile.txt.

You could stream the logfile running less and pressing SHIFT + F, and it will stream the file using less.

If you use watch, try the -n option to control the interval between each update, so the following would call tail every 2 seconds: $ watch -n 2 tail -n 15 mylogfile.txt; while this one polls it every 1 second: $ watch -n 1 tail -n 15 mylogfile.txt.

You can use the -d parameter: watch -d.


Question: is there a one-liner that allows me to create a directory and move into it at the same time?

Response: The command `mkdir longtitleproject && cd $_` allows the creation of a directory and immediate navigation into it using the `$_` variable in bash, which refers to the last argument of the previously executed command.


Question: how create a temporary file in shell script?

Response:
Use mktemp to create a temporary file `temp_file=$(mktemp)` or, alternatively, to create a temporary directory: `temp_dir=$(mktemp -d)`.
At the end of the script you have to delete the temporary file or directory `rm ${temp_file} rm -R ${temp_dir} mktemp`.


Question: how do i delete photos from my phone without deleting from icloud?

Response:
If you want to delete images from an iPhone or any device without deleting it from all your devices, you have to disable iCloud Photo Library and use another form of sync or another service, like Dropbox, Google Photos, or Amazon Cloud Drive.

However, if you turn on Optimize [device] Storage, iCloud Photo Library will automatically manage the size of your library on your device and free up space by keeping low-res versions of your pictures.


Question: secure way of masking out sensitive information in screenshots?

Response:
To effectively redact sensitive information from an image, it is recommended to utilize the Fill tool in MS Paint or a similar non-transparent covering method.
Ensuring that the covering method used doesn't leave any room for data to be visible upon zooming in is also vital, as simply zooming in could reveal the redacted information.
Moreover, the size of the masked area can lead to the recovery of the text through statistical analysis, especially if there is unmasked text before and after the redaction.
To ensure absolute certainty, completely eliminate sensitive data from the original file and save it as a new file.
It's also suggested to use an image editor that covers the area non-transparently to prevent recovery.


Question: what is the difference between data and storage on an iphone?

Response: There's no difference, other than the storage capacity.


Question: can visa gift cards be traced?

Response:
Visa gift cards can be traced due to the fact that purchases made with the card are tracked.
Furthermore, every transaction is reviewable via Go Wallet or vanilla VISA.


Question: how do i handle disagreement in a code review regarding an unlikely edge case?

Response:
When contending with code reviews concerning business strategy, having a conversation with someone knowledgeable in business strategy could be beneficial, especially if a difference in understanding persists.
To enhance the business utility of code reviews, one could categorize comments by type, ranging from critical fixes to optional improvements.


Question: how can i trigger a notification center notification from an applescript or shell script?

Response:
You can do this with Growl2, cocoaDialog, AppleScript's display notification (Mavericks or later), or by changing a setting in System Preference.
Or fork terminal-notifier to build a command line tool to display notification Alerts (with actions) and Reply Type Alerts.
To show a notification, provide the display notification command with a string to display.
Options are: cmd = %Q|osascript -e 'display notification (ruby script on OS X); or #!/bin/bash X="$*" /usr/bin/osascript -e 'display notification system attribute "X"'.


Question: how to clean log file?

Response:
There are several methods to empty a logfile, such as using commands like `> logfile or cat /dev/null > logfile` or `true | tee logfile`, which will truncate the logfile to zero size.
Additionally, one can use the `truncate --size 0 logfile` or `truncate -s0 logfile`  or use `rm logfile`, where it's assumed that the application will recreate it if it doesn't exist.
In cases where many files need to be emptied, the `find` command can be used to match and execute a zeroing command on the matched files or to delete them.


Question: i found unknown php code on my server. how do i de-obfuscate the code?

Response:
To de-obfuscate PHP files safely, you should not attempt the process on your web server.
PHP.ini includes a disable_functions feature that lets you choose which parts of the functionality to block, providing a way to selectively restrict access to specific functions.


Question: what is the difference between iterative and incremental development?

Response:
The Waterfall Model is a traditional incremental development approach that uses a set number of steps and development goes from start to finish in a linear path of progression.
Contrary to this, the Iterative Approach does not prescribe a specific number of steps; it evolves through repetitive cycles.


Question: why most people use 256 bit encryption instead of 128 bit?

Response:
There is a common perception that larger key sizes automatically imply greater security, which is not true, since the complexity of cryptographic algorithms can be influenced by other factors, such as implementation weaknesses.
Historical developments and regulatory inertia have led to the adoption of various key sizes for encryption, with the choice often influenced by perceived security needs rather than actual security requirements.
The National Institute of Standards and Technology's draft recommendations for post-quantum cryptography include the use of 256-bit keys.