NAME

       fork, wait, waitpid - basic process management

SYNOPSIS

       @load "fork"

       pid = fork()

       ret = waitpid(pid)

       ret = wait();

DESCRIPTION

       The fork extension adds three functions, as follows.

       fork() 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,   ERRNO   indicates   the   problem.    In  the  child,  PROCINFO["pid"]  and
              PROCINFO["ppid"] are updated to reflect the correct values.

       waitpid()
              This function takes a numeric argument, which is the process-id to  wait  for.  The
              return value is that of the waitpid(2) system call.

       wait() This  function  waits  for the first child to die.  The return value is that of the
              wait(2) system call.

BUGS

       There is no corresponding exec() function.

       The interfaces could be enhanced to provide more facilities,  including  pulling  out  the
       various bits of the return status.

EXAMPLE

       @load "fork"
       ...
       if ((pid = fork()) == 0)
           print "hello from the child"
       else
           print "hello from the parent"

SEE ALSO

       GAWK:  Effective AWK Programming, filefuncs(3am), fnmatch(3am), inplace(3am), ordchr(3am),
       readdir(3am), readfile(3am), revoutput(3am), rwarray(3am), time(3am).

       fork(2), wait(2), waitpid(2).

AUTHOR

       Arnold Robbins, arnold@skeeve.com.

COPYING PERMISSIONS

       Copyright © 2012, 2013, 2018, Free Software Foundation, Inc.

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