From 4c78d46018e699148c9944dd261424ee9a0e922e Mon Sep 17 00:00:00 2001 From: Daniel Beckham Date: Fri, 14 Sep 2001 20:57:26 +0000 Subject: [PATCH] initial draft of process control functions... several functions are still not documented, intro is not completed and several examples are missing. This file has not yet been added to manual.xml.in. git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@57556 c90b9560-bf6c-de11-be94-00142212c4b1 --- functions/pcntl.xml | 360 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 360 insertions(+) create mode 100644 functions/pcntl.xml 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. + + + + + + + +