WaitPid

Wait for a process to terminate

Declaration

Source position: oldlinux.pp line 1354

function WaitPid(

Pid: LongInt;

Status: pointer;

Options: LongInt

):LongInt;

WaitPid waits for a child process with process ID Pid to exit. The value of Pid can be one of the following:

Pid < -1: Causes WaitPid to wait for any child process whose process group ID equals the absolute value of pid.
Pid = -1: Causes WaitPid to wait for any child process.
Pid = 0: Causes WaitPid to wait for any child process whose process group ID equals the one of the calling process.
Pid > 0: Causes WaitPid to wait for the child whose process ID equals the value of Pid.

The Options parameter can be used to specify further how WaitPid behaves:

WNOHANG: Causes Waitpid to return immediately if no child hasexited.
WUNTRACED: Causes WaitPid to return also for children which are stopped, but whose status has not yet been reported.
__WCLONE: Causes WaitPid also to wait for threads created by the Clone call.

Upon return, it returns the exit status of the process, or -1 in case of failure.

For an example, see Fork.

Errors are returned in LinuxError.

Fork		Create child process
Execve		Execute process using environment