diff --git a/functions/pcntl.xml b/functions/pcntl.xml new file mode 100644 index 0000000000..8982a53e7a --- /dev/null +++ b/functions/pcntl.xml @@ -0,0 +1,360 @@ + + + + Process Control Functions + PCNTL + + + Process Control support in PHP is not enabled by default. You + will need to use the --enable-pcntl + configuration option when compiling PHP to enable Process Control + support. + + + The following list of signals are supported by the Process Control + functions. Please see your systems signal(7) man page for details + of the default behavior of these signals. + + Supported Signals + + + + SIG_IGN + SIGFPE + SIGCONT + + + SIG_DFL + SIGKILL + SIGSTOP + + + SIG_ERR + SIGUSR1 + SIGTSTP + + + SIGHUP + SIGUSR2 + SIGTTIN + + + SIGINT + SIGSEGV + SIGTTOU + + + SIGQUIT + SIGPIPE + SIGURG + + + SIGILL + SIGALRM + SIGXCPU + + + SIGTRAP + SIGTERM + SIGXFSZ + + + SIGABRT + SIGSTKFLT + SIGVTALRM + + + SIGIOT + SIGCHLD + SIGPROF + + + SIGBUS + SIGCLD + SIGWINCH + + + SIGPOLL + SIGIO + SIGPWR + + + SIGSYS + + + + + +
+ + + + + Process Control Example + + This example forks off a daemon process with a signal handler. + + + Process Control Example + +<?php + +$pid = pcntl_fork(); +if ($pid == -1) { + die("could not fork"); +} else if ($pid) { + exit(); // we are the parent +} else { + // we are the child +} + +// detatch from the controlling terminal +if (!posix_setsid()) { + die("could not detach from terminal"); +} + +// setup signal handlers +pcntl_signal(SIGTERM, "sig_handler"); +pcntl_signal(SIGHUP, "sig_handler"); + +// loop forever performing tasks +while(1) { + + // do something interesting here + +} + + +function sig_handler($signo) { + + switch($signo) { + case SIGTERM: + // handle shutdown tasks + exit; + break; + case SIGHUP: + // handle restart tasks + break; + default: + // handle all other signals + } + +} + + +?> + + + + + + + + + pcntl_fork + Forks the currently running process + + + Description + + + int pcntl_fork + + + + + The pcntl_fork function creates a child + process that differs from the parent process only in it's PID and + PPID. Please see your system's fork(2) man page for specific details as to + how fork works on your system. + + + On success, the PID of the child process is returned in the + parent's thread of execution, and a 0 is returned in the child's + thread of execution. On failure, a -1 will be returned in the + parent's context, no child process will be created, and a PHP + error is raised. + + + See also pcntl_waitpid and + pcntl_signal. + + + + + + + + pcntl_waitpid + Waits on or returns the status of a forked child + + + Description + + + int pcntl_waitpid + int pid + int status + int options + + + + The pcntl_waitpid function suspends execution + of the current process until a child as specified by the + pid argument has exited, or until a signal + is delivered whose action is to terminate the current process or + to call a signal handling function. If a child as requested by + pid has already exited by the time of the + call (a so-called "zombie" process), the function returns + immediately. Any system resources used by the child are + freed. Please see your system's waitpid(2) man page for specific + details as to how waitpid works on your system. + + + pcntl_waitpid returns the process ID of the + child which exited, -1 on error or zero if WNOHANG was used and no + child was available + + + The value of pid can be one of the following: + + + < -1 + + + wait for any child process whose process group ID is equal to + the absolute value of pid. + + + + + -1 + + + wait for any child process; this is the same behaviour that + the wait function exhibits. + + + + + 0 + + + wait for any child process whose process group ID is equal to + that of the calling process. + + + + + > 0 + + + wait for the child whose process ID is equal to the value of + pid. + + + + + + + pcntl_waitpid will store status information + in the status parameter which can be + evaluated using the following functions: + pcntl_wifexited, + pcntl_wifstopped, + pcntl_wifsignaled, + pcntl_wexitstatus, + pcntl_wtermsig and + pcntl_wstopsig. + + + The value of options is the value of zero + or more of the following two global constants + ORed together: + + + WNOHANG + + + return immediately if no child has exited. + + + + + WUNTRACED + + + return for children which are stopped, and whose status has + not been reported. + + + + + + + See also pcntl_fork, + pcntl_signal, + pcntl_wifexited, + pcntl_wifstopped, + pcntl_wifsignaled, + pcntl_wexitstatus, + pcntl_wtermsig and + pcntl_wstopsig. + + + + + + + + pcntl_signal + Installs a signal handler + + + Description + + + bool pcntl_signal + int signo + mixed handle + + + + The pcntl_signal function installs a new + signal handler for the signal indicated by + signo. The signal handler is set to + handler which may be the name of a user + created function, or either of the two global constants SIG_IGN + or SIG_DFL. + + + pcntl_signal returns &true; on success or + &false; on failure. + + + See also pcntl_fork and + pcntl_waitpid. + + + + + + + +