How Can I Asynchronously Execute Shell Commands in PHP?
Executing Shell Commands Asynchronously
Asynchronous execution of shell commands can be achieved by redirecting the output to a file and running the command in the background.
Shell Command Execution with Shell_exec
The shell_exec function runs a command line program and returns its output. However, it blocks the PHP script until the command completes execution.
Asynchronous Execution without Shell_exec
To execute a command asynchronously without blocking, you can use the following trick:
- Redirect Output: Redirect the standard output and standard error of the command to /dev/null. This suppresses the output from appearing in the PHP script.
- Run the Command in the Background: Add & to the end of the command to indicate that it should be run in the background.
Example:
shell_exec('php measurePerformance.php 47 844 [email protected] > /dev/null 2>&1 &');
By combining these techniques, you can execute commands asynchronously without waiting for them to complete. This allows your PHP script to continue running without getting blocked by the execution of the shell command.
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