view toys/oneit.c @ 90:7c77c6ec17ee

Add "make defconfig". Modify global options to start with CONFIG_TOYBOX_.
author Rob Landley <>
date Wed, 31 Jan 2007 14:37:01 -0500
parents c1f4f9101af7
children 1e8f4b05cb65
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/* oneit.c, tiny one-process init replacement.
 * Copyright 2005 by Rob Landley <>.

#include "toys.h"
#include <sys/reboot.h>

// The minimum amount of work necessary to get ctrl-c and such to work is:
// - Fork a child (PID 1 is special: can't exit, has various signals blocked).
// - Do a setsid() (so we have our own session).
// - In the child, attach stdio to /dev/tty0 (/dev/console is special)
// - Exec the rest of the command line.
// PID 1 then reaps zombies until the child process it spawned exits, at which
// point it calls sync() and reboot().  I could stick a kill -1 in there.

int oneit_main(void)
  int i;
  pid_t pid;

  // Create a new child process.
  pid = vfork();
  if (pid) {

    // pid 1 just reaps zombies until it gets its child, then halts the system.
    while (pid!=wait(&i));
    reboot(toys.optflags ? RB_POWER_OFF : RB_AUTOBOOT);
  // Redirect stdio to /dev/tty0, with new session ID, so ctrl-c works.
  for (i=0; i<3; i++) {

  // Can't xexec() here because we vforked so we don't want to error_exit().
  execvp(*toys.optargs, toys.optargs);