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/*
* from A simple program that can be used as the "receiver"
* part of a TCP network stream connection. It could
* be used for setting up inter-machine network pipes
* for programs like "tar"...
*
* Usage: from [-p] [-v] portno
*
* Version: @(#)from 1.00 11/06/92 FvK
*
* Author: Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <errno.h>
#include <netdb.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
static char *Version = "@(#)from 1.00 (11/06/92)";
extern int getopt(), optind, opterr;
void pr_sock(struct sockaddr_in *sip, int ports)
{
if (ports == 1) {
fprintf(stderr, "%u,%u,%u,%u,%u,%u\n",
((sip->sin_addr.s_addr >> 0) & 255),
((sip->sin_addr.s_addr >> 8) & 255),
((sip->sin_addr.s_addr >> 16) & 255),
((sip->sin_addr.s_addr >> 24) & 255),
((sip->sin_port >> 0) & 255),
((sip->sin_port >> 8) & 255));
} else fprintf(stderr, "%s:%u\n",
inet_ntoa(sip->sin_addr), ntohs(sip->sin_port));
}
void usage(void)
{
fprintf(stderr, "Usage: fromport [-p] [-v] port\n");
exit(-1);
}
int main(argc, argv)
int argc;
char *argv[];
{
char hostname[128], buff[1024];
struct sockaddr_in sin, him;
struct hostent *hp;
int opt_p = 0;
int opt_v = 0;
#if !defined(__GLIBC__)
int i, j, s;
#else /* __GLIBC__ */
size_t i;
int j, s;
#endif /* __GLIBC__ */
opterr = 0;
while((i = getopt(argc, argv, "pv")) != EOF) switch(i) {
case 'p':
opt_p = 1;
break;
case 'v':
opt_v = 1;
break;
default:
usage();
}
/* One more argument required. */
if (optind != (argc - 1)) usage();
/* Fetch port number. */
i = atoi(argv[optind]);
/* Fetch our hostname. */
if (gethostname(hostname, 128) < 0) {
perror("gethostname");
exit(-1);
}
/* Convert that to an IP address. */
if ((hp = gethostbyname(hostname)) == (struct hostent *)NULL) {
herror(hostname);
exit(-1);
}
memcpy((char *) &sin.sin_addr, hp->h_addr_list[0], hp->h_length);
strcpy(hostname, hp->h_name);
sin.sin_family = AF_INET;
sin.sin_port = htons(i);
if (opt_v ==1 ) {
fprintf(stderr, "Listening to ");
pr_sock(&sin, opt_p);
}
/* Create a socket. */
if ((s = socket(sin.sin_family, SOCK_STREAM, 0)) < 0) {
perror("socket");
exit(-1);
}
/* All done. Bind it to our address. */
if (bind(s, (struct sockaddr *) &sin, sizeof(sin)) < 0) {
perror("bind");
(void) close(s);
exit(-1);
}
/* Bind was OK. Now post a listen... */
if (listen(s, 1) < 0) {
perror("listen");
(void) close(s);
exit(-1);
}
/* Done. Await a connection! */
i = sizeof(him);
if ((j = accept(s, (struct sockaddr *) &him, &i)) < 0) {
perror("accept");
(void) close(s);
exit(-1);
}
/* We now have a valid connection. */
if (opt_v == 1) {
fprintf(stderr, "Incoming connection from ");
pr_sock(&him, opt_p);
}
/* Start receiving data until there is no more... */
do {
if ((i = read(j, buff, 1024)) <= 0) break;
(void) write(1, buff, i);
} while(1);
/* Check for any errors.. */
if (i != 0) {
fprintf(stderr, "Transfer aborted: %s\n", sys_errlist[errno]);
}
/* Close up! */
(void) close(j);
(void) close(s);
return(0);
}
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