02-11-2004
getpid() will return your pid.
getppid() will return your parent's pid.
There is no such thing as a getcpid() to return your child's pid. How could there be? You might have many children. The value returned by wait() is the pid the the particular child that died. There is no other way to get that pid besides one of the wait calls.
The termination status is generally the parameter to exit(). The child does a exit(2), you get a termination status of 2. It can also be a funky value if the process dies because of the default action of a signal.
The parent runs until it hits an exits, or it returns from main(), or it dies as a result of the default action of a signal.
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LEARN ABOUT DEBIAN
explain_wait_or_die
explain_wait_or_die(3) Library Functions Manual explain_wait_or_die(3)
NAME
explain_wait_or_die - wait for process to change state and report errors
SYNOPSIS
#include <libexplain/wait.h>
void explain_wait_or_die(int *status);
DESCRIPTION
The explain_wait_or_die function is used to call the wait(2) system call. On failure an explanation will be printed to stderr, obtained
from explain_wait(3), and then the process terminates by calling exit(EXIT_FAILURE).
This function is intended to be used in a fashion similar to the following example:
explain_wait_or_die(status);
status The status, exactly as to be passed to the wait(2) system call.
Returns:
This function only returns on success. On failure, prints an explanation and exits.
SEE ALSO
wait(2) wait for process to change state
explain_wait(3)
explain wait(2) errors
exit(2) terminate the calling process
COPYRIGHT
libexplain version 0.52
Copyright (C) 2008 Peter Miller
explain_wait_or_die(3)