workbench/network/stacks/AROSTCP/netlib/set_socket_stdio.c

   1 /* $Id$
   2  *
   3  *      set_socket_stdio.c - redirect stdio to/from a socket
   4  *
   5  *      Copyright © 1994 AmiTCP/IP Group,
   6  *                       Network Solutions Development Inc.
   7  *                       All rights reserved.
   8  */
   9
  10 /****** net.lib/set_socket_stdio ****************************************
  11
  12     NAME
  13         set_socket_stdio - redirect stdio to/from a socket
  14
  15     SYNOPSIS
  16         int set_socket_stdio(int sock);
  17
  18     FUNCTION
  19         Redirect stdio (stdin, stdout and stderr) to/from socket 'sock'.
  20         This is done by dup2()'ing 'sock' to the level 1 files underneath
  21         the stdin, stdout and stderr.
  22
  23         The original 'sock' reference is closed on successful return, so
  24         the socket descriptor given as argument should not be used after
  25         this function returns (successfully).
  26
  27     RETURN VALUES
  28         0 if successful, -1 on error. Global variable 'errno' contains
  29         the specific error code set by the failing function.
  30
  31     NOTES
  32         This module pulls in the link library stdio modules.
  33
  34     SEE ALSO
  35         dup2()
  36 *****************************************************************************
  37 *
  38 */
  39
  40 #include <bsdsocket.h>
  41
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44
  45 int
  46 set_socket_stdio(int sock)
  47 {
  48   /*
  49    * Replace the stdio with the sock
  50    */
  51   if (sock >= 0
  52       && dup2(sock, fileno(stdin)) >= 0
  53       && dup2(sock, fileno(stdout)) >= 0
  54       && dup2(sock, fileno(stderr)) >= 0)
  55     {
  56       /*
  57        * line buffered mode
  58        */
  59       setvbuf(stdin, NULL, _IOLBF, 0);
  60       setvbuf(stdout, NULL, _IOLBF, 0);
  61       setvbuf(stderr, NULL, _IOLBF, 0);
  62       /*
  63        * Close the original reference to the sock if necessary
  64        */
  65       if (sock > fileno(stderr))
  66         CloseSocket(sock);
  67
  68       return 0;
  69     }
  70   return -1;
  71 }