glibc/manual/examples/filesrv.c

66 lines
1.7 KiB
C

/* Datagram Socket Example
Copyright (C) 1991-2020 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 2
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 <https://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <sys/un.h>
#define SERVER "/tmp/serversocket"
#define MAXMSG 512
int
main (void)
{
int sock;
char message[MAXMSG];
struct sockaddr_un name;
size_t size;
int nbytes;
/* Remove the filename first, it's ok if the call fails */
unlink (SERVER);
/* Make the socket, then loop endlessly. */
sock = make_named_socket (SERVER);
while (1)
{
/* Wait for a datagram. */
size = sizeof (name);
nbytes = recvfrom (sock, message, MAXMSG, 0,
(struct sockaddr *) & name, &size);
if (nbytes < 0)
{
perror ("recfrom (server)");
exit (EXIT_FAILURE);
}
/* Give a diagnostic message. */
fprintf (stderr, "Server: got message: %s\n", message);
/* Bounce the message back to the sender. */
nbytes = sendto (sock, message, nbytes, 0,
(struct sockaddr *) & name, size);
if (nbytes < 0)
{
perror ("sendto (server)");
exit (EXIT_FAILURE);
}
}
}