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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WAIT(1) BSD General Commands Manual WAIT(1)
NAME
wait -- await process completion
SYNOPSIS
wait [pid]
DESCRIPTION
If invoked with no arguments, the wait utility waits until all existing child processes in the background have terminated.
Available operands:
pid If a pid operand is specified, and it is the process ID of a background child process that still exists, the wait utility waits until
that process has completed and consumes its status information, without consuming the status information of any other process.
If a pid operand is specified that is not the process ID of a child background process that still exists, wait exits without waiting
for any processes to complete.
The wait utility exits with one of the following values:
0 The wait utility was invoked with no operands and all of the existing background child processes have terminated, or the process
specified by the pid operand exited normally with 0 as its exit status.
>0 The specified process did not exist and its exit status information was not available, or the specified process existed or its exit
status information was available, and it terminated with a non-zero exit status.
If the specified process terminated abnormally due to the receipt of a signal, the exit status information of wait contains that termination
status as well.
STANDARDS
The wait command is expected to be IEEE Std 1003.2 (``POSIX.2'') compatible.
BSD
June 5, 1993 BSD