PCNTL_WAIT(3) 1 PCNTL_WAIT(3)
pcntl_wait - Waits on or returns the status of a forked child
SYNOPSIS
int pcntl_wait (int &$status, [int $options])
DESCRIPTION
The wait function suspends execution of the current process until a child has exited, or until a signal is delivered whose action is to
terminate the current process or to call a signal handling function. If a child has already exited by the time of the call (a so-called
"zombie" process), the function returns immediately. Any system resources used by the child are freed. Please see your system's wait(2) man
page for specific details as to how wait works on your system.
Note
This function is equivalent to calling pcntl_waitpid(3) with a -1$pid and no $options.
PARAMETERS
o $status
-pcntl_wait(3) will store status information in the $status parameter which can be evaluated using the following functions:
pcntl_wifexited(3), pcntl_wifstopped(3), pcntl_wifsignaled(3), pcntl_wexitstatus(3), pcntl_wtermsig(3) and pcntl_wstopsig(3).
o $options
- If wait3 is available on your system (mostly BSD-style systems), you can provide the optional $options parameter. If this param-
eter is not provided, wait will be used for the system call. If wait3 is not available, providing a value for $options
will have no effect. The value of $options
is the value of zero or more of the following two constants OR'ed together:
Possible values for $options
+----------+---------------------------------------------------+
| | |
| WNOHANG | |
| | |
| | Return immediately if no child has exited. |
| | |
| | |
|WUNTRACED | |
| | |
| | Return for children which are stopped, and whose |
| | status has not been reported. |
| | |
+----------+---------------------------------------------------+
RETURN VALUES
pcntl_wait(3) returns the process ID of the child which exited, -1 on error or zero if WNOHANG was provided as an option (on wait3-avail-
able systems) and no child was available.
SEE ALSO
pcntl_fork(3), pcntl_signal(3), pcntl_wifexited(3), pcntl_wifstopped(3), pcntl_wifsignaled(3), pcntl_wexitstatus(3), pcntl_wtermsig(3),
pcntl_wstopsig(3), pcntl_waitpid(3).
PHP Documentation Group PCNTL_WAIT(3)
