| /* | |
| Write to file using FileIO classes. | |
| This sketch demonstrate how to write file into the YunShield/Yún filesystem. | |
| A shell script file is created in /tmp, and it is executed afterwards. | |
| created 7 June 2010 | |
| by Cristian Maglie | |
| This example code is in the public domain. | |
| http://www.arduino.cc/en/Tutorial/FileWriteScript | |
| */ | |
| void setup() { | |
| // Setup Bridge (needed every time we communicate with the Arduino Yún) | |
| Bridge.begin(); | |
| // Initialize the Serial | |
| SerialUSB.begin(9600); | |
| while (!SerialUSB); // wait for Serial port to connect. | |
| SerialUSB.println("File Write Script example\n\n"); | |
| // Setup File IO | |
| FileSystem.begin(); | |
| // Upload script used to gain network statistics | |
| uploadScript(); | |
| } | |
| void loop() { | |
| // Run stats script every 5 secs. | |
| runScript(); | |
| delay(5000); | |
| } | |
| // this function creates a file into the linux processor that contains a shell script | |
| // to check the network traffic of the WiFi interface | |
| void uploadScript() { | |
| // Write our shell script in /tmp | |
| // Using /tmp stores the script in RAM this way we can preserve | |
| // the limited amount of FLASH erase/write cycles | |
| File script = FileSystem.open("/tmp/wlan-stats.sh", FILE_WRITE); | |
| // Shell script header | |
| script.print("#!/bin/sh\n"); | |
| // shell commands: | |
| // ifconfig: is a command line utility for controlling the network interfaces. | |
| // wlan0 is the interface we want to query | |
| // grep: search inside the output of the ifconfig command the "RX bytes" keyword | |
| // and extract the line that contains it | |
| script.print("ifconfig wlan0 | grep 'RX bytes'\n"); | |
| script.close(); // close the file | |
| // Make the script executable | |
| Process chmod; | |
| chmod.begin("chmod"); // chmod: change mode | |
| chmod.addParameter("+x"); // x stays for executable | |
| chmod.addParameter("/tmp/wlan-stats.sh"); // path to the file to make it executable | |
| chmod.run(); | |
| } | |
| // this function run the script and read the output data | |
| void runScript() { | |
| // Run the script and show results on the Serial | |
| Process myscript; | |
| myscript.begin("/tmp/wlan-stats.sh"); | |
| myscript.run(); | |
| String output = ""; | |
| // read the output of the script | |
| while (myscript.available()) { | |
| output += (char)myscript.read(); | |
| } | |
| // remove the blank spaces at the beginning and the ending of the string | |
| output.trim(); | |
| SerialUSB.println(output); | |
| SerialUSB.flush(); | |
| } | |