fork.c
author Markus Bröker <mbroeker@volpe.spectre.org>
Wed, 18 Aug 2010 16:14:40 +0200
changeset 140 05d42a3737a4
parent 139 cb1d3f4cf18e
permissions -rw-r--r--
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/**
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 * fork.c
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 * Copyright (C) 2008 Markus Broeker
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 */
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <sys/wait.h>
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#include <errno.h>
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int fork_proc (char **argv, char **argp)
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{
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    int pid;
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    char *cmd = argv[0];
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    pid = fork ();
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    switch (pid) {
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    case 0:
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        printf ("Starting new Process\n");
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cb1d3f4cf18e execve returns a value on error and this catches it
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        execve (cmd, argv, argp);
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        exit (EXIT_FAILURE);
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    case -1:
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        perror ("FORK");
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        return errno;
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    default:
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        printf ("Pid started as %d\n", pid);
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        wait (&pid);
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        printf ("Exit-Status = %d\n", pid);
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dff18d1ac2af Compatibility: We support Linux and BSD
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        return pid;
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    }
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    // should never happen
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    return -1;
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}
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int main (int argc, char **argv)
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{
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    char *args[] = {
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        "/bin/ls",
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        "-al",
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        NULL
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    };
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    if (fork_proc (args, NULL) == 0) {
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        printf ("It just works :P\n");
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    }
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    return EXIT_SUCCESS;
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}