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/* Test of opening a subcommand stream.
Copyright (C) 2009 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* Written by Eric Blake <ebb9@byu.net>, 2009. */
/* Include <config.h> and a form of <stdio.h> first. */
/* Helpers. */
#include <stdlib.h>
#include <string.h>
#include <sys/wait.h>
#include <unistd.h>
#define ASSERT(expr) \
do \
{ \
if (!(expr)) \
{ \
fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
fflush (stderr); \
abort (); \
} \
} \
while (0)
int
main (int argc, char **argv)
{
size_t len;
char *cmd;
int i;
/* Children - use the pipe. */
if (argc > 1)
{
if (*argv[1] == 'r') /* Parent is reading, so we write. */
ASSERT (putchar ('c') == 'c');
else /* Parent is writing, so we read. */
ASSERT (getchar () == 'p');
/* Test that parent can read non-zero status. */
return 42;
}
/* Parent - create read and write child, once under normal
circumstances and once with stdin and stdout closed. */
len = strlen (argv[0]);
cmd = malloc (len + 3); /* Adding " r" and NUL. */
ASSERT (cmd);
/* We count on argv[0] not containing any shell metacharacters. */
strcpy (cmd, argv[0]);
cmd[len] = ' ';
cmd[len + 2] = '\0';
for (i = 0; i < 2; i++)
{
FILE *child;
int status;
if (i)
{
ASSERT (fclose (stdin) == 0);
ASSERT (fclose (stdout) == 0);
}
cmd[len + 1] = 'r';
ASSERT (child = popen (cmd, "r"));
ASSERT (fgetc (child) == 'c');
status = pclose (child);
ASSERT (WIFEXITED (status));
ASSERT (WEXITSTATUS (status) == 42);
if (i)
{
ASSERT (dup2 (STDIN_FILENO, STDIN_FILENO) == -1);
ASSERT (dup2 (STDOUT_FILENO, STDOUT_FILENO) == -1);
}
cmd[len + 1] = 'w';
ASSERT (child = popen (cmd, "w"));
ASSERT (fputc ('p', child) == 'p');
status = pclose (child);
ASSERT (WIFEXITED (status));
ASSERT (WEXITSTATUS (status) == 42);
if (i)
{
ASSERT (dup2 (STDIN_FILENO, STDIN_FILENO) == -1);
ASSERT (dup2 (STDOUT_FILENO, STDOUT_FILENO) == -1);
}
}
free (cmd);
return 0;
}
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