[php-src] Issue #11871: proc_get_status exitcode is -1 after setting SIGCHLD

Issue: https://github.com/php/php-src/issues/11871 Author: campbsb ### Description After setting SIGCHLD, proc_get_status() returns unreliable exitcode values On both el7 PHP 8.1.21 and el8 PHP 8.2122, setting SIGCHLD to SIG_IGN results in proc_get_status returning exitcode -1. See https://stackoverflow.com/questions/71354900/php-proc-get-status-exitcode-is-always-1-after-pcntl-fork On el8 PHP 8.1.22, setting SIGCHLD to a signal handler results in proc_get_status returning exitcode -1, but el7 PHP 8.1.21 works correctly. ``` #!/usr/bin/env php <?php function handleSIGCHLD($signo) { } //pcntl_signal(SIGCHLD, 'handleSIGCHLD'); pcntl_signal(SIGCHLD, SIG_IGN); $proc = proc_open("/usr/bin/sleep 1", [['pipe', 'r'], ['pipe', 'w'], ['pipe', 'w']], $pipes); do { $status = proc_get_status($proc); if (! $status['running']) break; usleep(300000); } while (true); echo "Exitcode: $status[exitcode]", PHP_EOL; ``` ### PHP Version PHP 8.1.21 and PHP 8.8.22 ### Operating System RHEL 8.8