Free Software Foundation
Feb 02 2018
fork, wait, waitpid - basic process management
pid = fork()
ret = waitpid(pid)
ret = wait();
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.|
|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.|
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.
@load "fork" ... if ((pid = fork()) == 0) print "hello from the child" else print "hello from the parent"
Arnold Robbins, arnold.
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