compiler/posixc/wait.c

   1 /*
   2     Copyright © 2004-2013, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #define DEBUG 0
   7
   8 #include <aros/debug.h>
   9 #include <proto/exec.h>
  10 #include <aros/debug.h>
  11
  12 #include <sys/types.h>
  13 #include <errno.h>
  14
  15 /*****************************************************************************
  16
  17     NAME */
  18 #include <sys/wait.h>
  19
  20         pid_t wait(
  21
  22 /*  SYNOPSIS */
  23         int *status)
  24
  25 /*  FUNCTION
  26         Waits for child process to change state. State change is one of the
  27         following events: child has exited, child was terminated by a signal,
  28         child was stopped by a signal, child was resumed by a signal.
  29
  30         The function stores status of the process that changed state in the
  31         pointer given as status argument.
  32
  33         The following macros can be used to extract information from the
  34         status value:
  35
  36         WIFEXITED(status)    - true if the process has exited
  37         WEXITSTATUS(status)  - exit status of the exited process
  38         WIFSIGNALED(status)  - true if the child process was terminated by a
  39                                signal
  40         WTERMSIG(status)     - number of the signal that caused process
  41                                termination
  42         WIFSTOPPED(status)   - true if the child process was stopped by a
  43                                signal
  44         WSTOPSIG(status)     - number of the signal that caused child process
  45                                stop
  46         WIFCONTINUED(status) - true if the child process was resumed by the
  47                                SIGCONT signal.
  48
  49         Parent process will be suspended until a child changes state. If a
  50         child process has already changed state, function returns immediately.
  51
  52     INPUTS
  53         status - Pointer to int where child return status will be stored or
  54         NULL if you don't want to store status.
  55
  56     RESULT
  57         Process id of the child process on success or -1 on error. If an error
  58         occurred, the global variable errno is set.
  59
  60     NOTES
  61         This function will work only for child processeses notifying parent
  62         process of their death, for example processes created by vfork() call.
  63         If you want to use it for other processes, remember to set the
  64         NP_NotifyOnDeath tag value to TRUE during child process creation.
  65
  66     EXAMPLE
  67
  68     BUGS
  69
  70     SEE ALSO
  71         waitpid()
  72
  73     INTERNALS
  74         Since POSIX signals are not yet implemented, WIFSIGNALED, WIFSTOPPED
  75         and WIFCONTINUED macros always return 0. WIFEXITED always returns 1.
  76
  77         The et_UniqueID field of the ETask structure is used as process id.
  78
  79 ******************************************************************************/
  80 {
  81     pid_t ret = -1;
  82     struct ETask *et;
  83
  84     D(bug("wait()\n"));
  85
  86     et = GetETask(FindTask(NULL));
  87     if(!et)
  88     {
  89         /* only ETasks are fertile */
  90         errno = ECHILD;
  91         return -1;
  92     }
  93
  94     et = (struct ETask *)ChildWait(0);
  95     if (et != (struct ETask *)CHILD_NOTNEW)
  96     {
  97         if(status)
  98         {
  99             *status = et->et_Result1;
 100         }
 101         ret = et->et_UniqueID;
 102         ChildFree(et->et_UniqueID);
 103     }
 104     else
 105         errno = ECHILD;
 106
 107     return ret;
 108 }