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/*
* RTFL
*
* Copyright 2014 Sebastian Geerken <sgeerken@dillo.org>
*
* 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/>.
*/
#include <unistd.h>
#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <sys/select.h>
static void syserr (const char *fmt, ...)
{
va_list args;
va_start (args, fmt);
vfprintf (stderr, fmt, args);
fprintf (stderr, ": %s\n", strerror (errno));
exit (1);
}
int main (int argc, char *argv[])
{
int parent2child[2];
char buf[2048];
ssize_t n;
if (pipe (parent2child) == -1) syserr ("pipe failed");
switch (fork ()) {
case -1:
syserr ("fork failed");
break;
case 0:
if (close (parent2child[1]) == -1)
syserr ("close(%d) failed", parent2child[0]);
if (close (0) == -1) syserr ("close(0) failed");
if (dup2 (parent2child[0], 0) == -1)
syserr ("dup2(%d, 0) failed", parent2child[0]);
if (close (parent2child[0]) == -1)
syserr ("close(%d) failed", parent2child[0]);
do {
if ((n = read (0, buf, sizeof (buf))) == -1) syserr ("read failed");
fprintf (stderr, "[child] %d bytes read\n", (int)n);
} while (n > 0);
break;
default:
if (close (parent2child[0]) == -1)
syserr ("close(%d) failed", parent2child[0]);
if (write (parent2child[1], "Hi!", 3) == -1) syserr ("write failed");
if (close (parent2child[1]) == -1)
syserr ("close(%d) failed", parent2child[0]);
break;
}
return 0;
}
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