stdio-common/test-popen.c

   1 /* Copyright (C) 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22
  23 void
  24 write_data (FILE *stream)
  25 {
  26   int i;
  27   for (i=0; i<100; i++)
  28     fprintf (stream, "%d\n", i);
  29   if (ferror (stream))  {
  30     fprintf (stderr, "Output to stream failed.\n");
  31     exit (1);
  32     }
  33 }
  34
  35 void
  36 read_data (FILE *stream)
  37 {
  38   int i, j;
  39
  40   for (i=0; i<100; i++)
  41     {
  42       if (fscanf (stream, "%d\n", &j) != 1 || j != i)
  43         {
  44           if (ferror (stream))
  45             perror ("fscanf");
  46           puts ("Test FAILED!");
  47           exit (1);
  48         }
  49     }
  50 }
  51
  52 int
  53 main (void)
  54 {
  55   FILE *output, *input;
  56   int wstatus, rstatus;
  57
  58   /* We must remove this entry to assure the `cat' binary does not use
  59      the perhaps incompatible new shared libraries.  */
  60   unsetenv ("LD_LIBRARY_PATH");
  61
  62   output = popen ("/bin/cat >/tmp/tstpopen.tmp", "w");
  63   if (output == NULL)
  64     {
  65       perror ("popen");
  66       puts ("Test FAILED!");
  67       exit (1);
  68     }
  69   write_data (output);
  70   wstatus = pclose (output);
  71   printf ("writing pclose returned %d\n", wstatus);
  72   input = popen ("/bin/cat /tmp/tstpopen.tmp", "r");
  73   if (input == NULL)
  74     {
  75       perror ("/tmp/tstpopen.tmp");
  76       puts ("Test FAILED!");
  77       exit (1);
  78     }
  79   read_data (input);
  80   rstatus = pclose (input);
  81   printf ("reading pclose returned %d\n", rstatus);
  82
  83   remove ("/tmp/tstpopen.tmp");
  84
  85   puts (wstatus | rstatus  ? "Test FAILED!" : "Test succeeded.");
  86   exit (wstatus | rstatus);
  87 }