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-rw-r--r--manual/examples/inetsrv.c103
1 files changed, 103 insertions, 0 deletions
diff --git a/manual/examples/inetsrv.c b/manual/examples/inetsrv.c
new file mode 100644
index 0000000..bd86e80
--- /dev/null
+++ b/manual/examples/inetsrv.c
@@ -0,0 +1,103 @@
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+
+#define PORT 5555
+#define MAXMSG 512
+
+int
+read_from_client (int filedes)
+{
+ char buffer[MAXMSG];
+ int nbytes;
+
+ nbytes = read (filedes, buffer, MAXMSG);
+ if (nbytes < 0)
+ {
+ /* Read error. */
+ perror ("read");
+ exit (EXIT_FAILURE);
+ }
+ else if (nbytes == 0)
+ /* End-of-file. */
+ return -1;
+ else
+ {
+ /* Data read. */
+ fprintf (stderr, "Server: got message: `%s'\n", buffer);
+ return 0;
+ }
+}
+
+int
+main (void)
+{
+ extern int make_socket (unsigned short int port);
+ int sock;
+ fd_set active_fd_set, read_fd_set;
+ int i;
+ struct sockaddr_in clientname;
+ size_t size;
+
+ /* Create the socket and set it up to accept connections. */
+ sock = make_socket (PORT);
+ if (listen (sock, 1) < 0)
+ {
+ perror ("listen");
+ exit (EXIT_FAILURE);
+ }
+
+ /* Initialize the set of active sockets. */
+ FD_ZERO (&active_fd_set);
+ FD_SET (sock, &active_fd_set);
+
+ while (1)
+ {
+ /* Block until input arrives on one or more active sockets. */
+ read_fd_set = active_fd_set;
+ if (select (FD_SETSIZE, &read_fd_set, NULL, NULL, NULL) < 0)
+ {
+ perror ("select");
+ exit (EXIT_FAILURE);
+ }
+
+ /* Service all the sockets with input pending. */
+ for (i = 0; i < FD_SETSIZE; ++i)
+ if (FD_ISSET (i, &read_fd_set))
+ {
+ if (i == sock)
+ {
+ /* Connection request on original socket. */
+ int new;
+ size = sizeof (clientname);
+ new = accept (sock,
+ (struct sockaddr *) &clientname,
+ &size);
+ if (new < 0)
+ {
+ perror ("accept");
+ exit (EXIT_FAILURE);
+ }
+ fprintf (stderr,
+ "Server: connect from host %s, port %hd.\n",
+ inet_ntoa (clientname.sin_addr),
+ ntohs (clientname.sin_port));
+ FD_SET (new, &active_fd_set);
+ }
+ else
+ {
+ /* Data arriving on an already-connected socket. */
+ if (read_from_client (i) < 0)
+ {
+ close (i);
+ FD_CLR (i, &active_fd_set);
+ }
+ }
+ }
+ }
+}