3 * Copyright (C) 2001-2003 Simone Piccardi
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or (at
8 * your option) any later version.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 /****************************************************************
22 * Simple TCP client for echo service (port 7)
24 * Author: Simone Piccardi
27 * Usage: echo -h give all info's
29 ****************************************************************/
31 * Include needed headers
33 #include <sys/types.h> /* primitive system data types */
34 #include <unistd.h> /* unix standard library */
35 #include <arpa/inet.h> /* IP addresses conversion utilities */
36 #include <sys/socket.h> /* socket constants, types and functions */
37 #include <stdio.h> /* standard I/O library */
38 #include <errno.h> /* error definitions and routines */
39 #include <string.h> /* C strings library */
45 void ClientEcho(FILE * filein, int socket);
46 void SigTERM_hand(int sig);
49 int main(int argc, char *argv[])
52 * Variables definition
56 struct sockaddr_in serv_add;
59 * Input section: decode parameters passed in the calling
62 opterr = 0; /* don't want writing to stderr */
63 while ( (i = getopt(argc, argv, "hr")) != -1) {
69 printf("Wrong -h option use\n");
76 case '?': /* unrecognized options */
77 printf("Unrecognized options -%c\n",optopt);
79 default: /* should not reached */
83 /* ***********************************************************
85 * Options processing completed
89 * ***********************************************************/
91 if ( (sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
92 perror("Socket creation error");
95 /* initialize address */
96 memset((void *) &serv_add, 0, sizeof(serv_add)); /* clear server address */
97 serv_add.sin_family = AF_INET; /* address type is INET */
98 serv_add.sin_port = htons(7); /* echo port is 7 */
99 /* build address using inet_pton */
100 if ( (inet_pton(AF_INET, argv[optind], &serv_add.sin_addr)) <= 0) {
101 perror("Address creation error");
104 /* extablish connection */
105 if (connect(sock, (struct sockaddr *)&serv_add, sizeof(serv_add)) < 0) {
106 perror("Connection error");
109 /* check if resetting on close is required */
111 printf("Setting reset on close \n");
114 if (setsockopt(sock, SOL_SOCKET, SO_LINGER, &ling, sizeof(ling))) {
115 perror("Cannot set linger");
119 /* do read/write operations */
120 ClientEcho(stdin, sock);
125 * routine to print usage info and exit
128 printf("Take daytime from a remote host \n");
130 printf(" daytime [-h] [-v] [host in dotted decimal form] \n");
131 // printf(" -v set verbosity on\n");
132 printf(" -r require reset on closing\n");
133 printf(" -h print this help\n");
137 void ClientEcho(FILE * filein, int socket)
139 char sendbuff[MAXLINE+1], recvbuff[MAXLINE+1];
144 /* initialize file descriptor set */
146 maxfd = max(fileno(filein), socket) + 1;
148 FD_SET(socket, &fset); /* set for the socket */
150 FD_SET(fileno(filein), &fset); /* set for the standard input */
152 select(maxfd, &fset, NULL, NULL, NULL); /* wait for read ready */
153 if (FD_ISSET(fileno(filein), &fset)) { /* if ready on stdin */
154 if (fgets(sendbuff, MAXLINE, filein) == NULL) { /* if no input */
155 eof = 1; /* EOF on input */
156 shutdown(socket, SHUT_WR); /* close write half */
157 FD_CLR(fileno(filein), &fset); /* no more interest on stdin */
158 } else { /* else we have to write to socket */
159 nwrite = FullWrite(socket, sendbuff, strlen(sendbuff));
160 if (nwrite < 0) { /* on error stop */
161 printf("Errore in scrittura: %s", strerror(errno));
166 if (FD_ISSET(socket, &fset)) { /* if ready on socket */
167 nread = read(socket, recvbuff, strlen(sendbuff)); /* do read */
168 if (nread < 0) { /* error condition, stop client */
169 printf("Errore in lettura: %s\n", strerror(errno));
172 if (nread == 0) { /* server closed connection, stop */
176 printf("EOF prematuro sul socket\n");
180 recvbuff[nread] = 0; /* else read is ok, write on stdout */
181 if (fputs(recvbuff, stdout) == EOF) {
182 perror("Errore in scrittura su terminale");