manual/examples/popen.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3
   4 void
   5 write_data (FILE * stream)
   6 {
   7   int i;
   8   for (i = 0; i < 100; i++)
   9     fprintf (stream, "%d\n", i);
  10   if (ferror (stream))
  11     {
  12       fprintf (stderr, "Output to stream failed.\n");
  13       exit (EXIT_FAILURE);
  14     }
  15 }
  16
  17 /*@group*/
  18 int
  19 main (void)
  20 {
  21   FILE *output;
  22
  23   output = popen ("more", "w");
  24   if (!output)
  25     {
  26       fprintf (stderr,
  27                "incorrect parameters or too many files.\n");
  28       return EXIT_FAILURE;
  29     }
  30   write_data (output);
  31   if (pclose (output) != 0)
  32     {
  33       fprintf (stderr,
  34                "Could not run more or other error.\n");
  35     }
  36   return EXIT_SUCCESS;
  37 }
  38 /*@end group*/