compiler/clib/pipe.c

   1 /*
   2     Copyright © 1995-2004, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include <proto/dos.h>
   7
   8 #include <unistd.h>
   9 #include <fcntl.h>
  10 #include <errno.h>
  11
  12 #include "__open.h"
  13
  14 static int clear_nonblock_flag (int desc)
  15 {
  16     int oldflags = fcntl(desc, F_GETFL, 0);
  17
  18     if (oldflags == -1)
  19         return -1;
  20
  21     oldflags &= ~O_NONBLOCK;
  22
  23     return fcntl(desc, F_SETFL, oldflags);
  24 }
  25
  26 int pipe(int *pipedes)
  27 {
  28     if (!pipedes)
  29     {
  30         errno = EFAULT;
  31
  32         return -1;
  33     }
  34
  35     pipedes[0] =  open("PIPEFS:__UNNAMED__", O_RDONLY|O_NONBLOCK);
  36     if (pipedes[0] != -1)
  37     {
  38         fdesc *desc = __getfdesc(pipedes[0]);
  39         BPTR olddir = CurrentDir(desc->fh);
  40
  41         if
  42         (
  43             clear_nonblock_flag(pipedes[0]) != -1 &&
  44             ((pipedes[1] = open("", O_WRONLY)) != -1)
  45         )
  46         {
  47             CurrentDir(olddir);
  48
  49             return 0;
  50         }
  51
  52         CurrentDir(olddir);
  53         close(pipedes[0]);
  54     }
  55
  56     return -1;
  57 }