PHP sapi_windows_set_ctrl_handler() Function
The PHP sapi_windows_set_ctrl_handler() function sets or removes a CTRL event handler, which allows Windows CLI processes to intercept or ignore CTRL+C and CTRL+BREAK events. Note that in multithreaded environments, this is only possible when called from the main thread.
Syntax
sapi_windows_set_ctrl_handler(handler, add)
Parameters
event |
handler(int $event): void event: The CTRL event which has been received - either PHP_WINDOWS_EVENT_CTRL_C or PHP_WINDOWS_EVENT_CTRL_BREAK. Setting a null handler causes the process to ignore CTRL+C events, but not CTRL+BREAK events. |
add |
Optional. If true, the handler is set. If false, the handler is removed. Default is true. |
Return Value
Returns true on success or false on failure.
Example: basic sapi_windows_set_ctrl_handler() usage
The example below shows how to pass along CTRL+BREAK events to a child process. In this case the child process echoes "Hello World!" every second, until the user presses CTRL+BREAK, what causes only the child process to be terminated.
<?php
//forwarding CTRL+BREAK events to the child process
sapi_windows_set_ctrl_handler('sapi_windows_generate_ctrl_event');
//creating a child process which echoes every second
$cmd = ['php', '-r', 'while (true) { echo "Hello World!\n"; sleep(1); }'];
$descspec = array(['pipe', 'r'], ['pipe', 'w'], ['pipe', 'w']);
$options = ['create_process_group' => true];
$proc = proc_open($cmd, $descspec, $pipes, null, null, $options);
while (true) {
echo fgets($pipes[1]);
}
?>
Example: sapi_windows_set_ctrl_handler() example
The example below shows how to intercept CTRL events.
<?php
function ctrl_handler(int $event) {
switch ($event) {
case PHP_WINDOWS_EVENT_CTRL_C:
echo "You have pressed CTRL+C\n";
break;
case PHP_WINDOWS_EVENT_CTRL_BREAK:
echo "You have pressed CTRL+BREAK\n";
break;
}
}
sapi_windows_set_ctrl_handler('ctrl_handler');
//infinite loop, so the handler can be triggered
while (true);
?>
❮ PHP Miscellaneous Reference
