Section: GNU Awk Extension Modules (3am)
Updated: Feb 02 2018
fork, wait, waitpid - basic process management
pid = fork()
ret = waitpid(pid)
ret = wait();
extension adds three functions, as follows.
This function creates a new process. The return value is the zero
in the child and the process-id number of the child in the parent,
or -1 upon error. In the latter case,
indicates the problem.
In the child, PROCINFO["pid"] and PROCINFO["ppid"]
are updated to reflect the correct values.
This function takes a numeric argument, which is the process-id to
wait for. The return value is that of the
This function waits for the first child to die.
The return value is that of the
There is no corresponding
The interfaces could be enhanced to provide more facilities,
including pulling out the various bits of the return status.
if ((pid = fork()) == 0)
print "hello from the child"
print "hello from the parent"
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