Current Location: Home> Latest Articles> What Are the Differences Between proc_terminate and proc_close Functions? How to Use Them Together More Efficiently?

What Are the Differences Between proc_terminate and proc_close Functions? How to Use Them Together More Efficiently?

M66 2025-08-11 
[What Are the Differences Between proc_terminate and proc_close Functions? How to Use Them Together More Efficiently?]
<p>In<span class="hljs-type">PHP programming,<span><code>proc_terminate

  • $process: The resource handle returned by proc_open pointing to the target process.

  • $signal: The signal sent to the target process, defaulting to SIGTERM, which requests the process to terminate gracefully.

proc_terminate is suitable for forcibly stopping a process, especially when it fails to end as expected. Typically, it terminates the process immediately without waiting for the process’s outcome. If you prefer a gentler way to stop a process, you can send the SIGTERM signal first. If this fails to stop the process, you may consider using SIGKILL to forcibly kill it.

2. proc_close Function

The proc_close function is used to close a process started via proc_open and retrieve its exit status. Its basic syntax is:

int proc_close(resource $process);

  • $process: The resource handle pointing to the target process.

This function waits for the process to exit and returns its exit status code. If the process completes successfully, it returns the exit status (usually 0); if the process exits with an error, it returns a non-zero value.

proc_close is mainly used to end a process and obtain its exit information. After the process finishes its task, this function should be called to close the process and retrieve the relevant exit status.

3. Differences Between proc_terminate and proc_close

  1. Behavior Differences:

    • proc_terminate immediately terminates the process, which may cause resources to not be fully released and the process to not exit normally.

    • proc_close waits for the process to exit naturally and returns the exit status, representing a normal way to end a process.

  2. Different Uses:

    • proc_terminate is used for forcibly stopping a process, especially when it fails to exit properly.

    • proc_close is used after the process ends normally, to get the exit status and close the process.

  3. Resource Release:

    • After using proc_terminate, process resources may not be fully released, so you should check and release them manually if needed.

    • Using proc_close releases process resources after exit, making it more suitable for regular process termination handling.

4. How to Use proc_terminate and proc_close Together More Efficiently?

To efficiently manage processes, it is recommended to combine proc_terminate and proc_close in the following scenarios:

  1. Normal Process Termination:
    If the process runs for a relatively short time and terminates normally, use proc_close directly. It waits for the process to exit and retrieves the exit status. No need to forcibly terminate the process in this case.

  2. Forced Process Termination:
    If the process runs for too long or hangs, first call proc_terminate to send the termination signal and forcibly stop the process. Then use proc_close to get the exit status and ensure resource cleanup.

  3. Timed Termination and Cleanup:
    If a process must finish within a specified time, combine proc_terminate and proc_close. Periodically check whether the process has timed out; if so, use proc_terminate to terminate it, then use proc_close to confirm the process status.

// Sample code
$process = proc_open('php some_script.php', $descriptorspec, </span>$pipes);
<p></span>// Wait for process to complete or check timeout<br>
$timeout = 30; </span>// Set timeout to 30 seconds<br>
$start_time = </span>time();</p>
<p></span>while (time() - $start_time < $timeout) {<br>
// Check if process is still running<br>
$status = proc_get_status($process);<br>
if (!$status['running']) {<br>
break;<br>
}<br>
sleep(1); // Wait 1 second before checking again<br>
}</p>
<p>// If process timed out, force terminate<br>
if (time() - $start_time >= $timeout) {<br>
proc_terminate($process);<br>
echo "Process terminated due to timeout.\n";<br>
}</p>
<p>$exit_code = proc_close($process);<br>
echo "Process exited with code: $exit_code\n";<br>
</span><br>

This approach ensures that the process exits normally whenever possible, while also providing timely resource cleanup in case of exceptions, preventing processes from occupying system resources.

5. Conclusion

  • proc_terminate is used to immediately terminate a process, with options to send different signals controlling how the process closes, but note it may not release all resources.

  • proc_close is used to properly close a process and obtain its exit status; it is recommended to use it after the process completes its task.

  • For more efficient external process management, you can first use proc_terminate to forcibly stop unresponsive processes, then use proc_close to clean up resources and get the exit status.

Mastering the differences between these two functions and how to use them together helps you flexibly control and manage child processes during development, improving program stability and efficiency.

Related