client.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/select.h>
#include <assert.h>

void checkError(int status,int line)
{
	if (status < 0) {
		printf("socket error(%d)-%d: [%s]\n",getpid(),line,strerror(errno));
		exit(-1);
	}
}

int main(int argc, char ** argv) {
	int sid = socket(PF_INET,SOCK_STREAM,0);
	struct sockaddr_in srv;
	struct hostent *server = gethostbyname("localhost");
	if (server==NULL) {
		printf("Couldn't find a host named: %s\n",argv[1]);
		return 2;
	}

	srv.sin_family = AF_INET;
	srv.sin_port   = htons(8025);
	memcpy(&srv.sin_addr,server->h_addr_list[0],server->h_length);
	int status = connect(sid,(struct sockaddr*)&srv,sizeof(srv));
	checkError(status,__LINE__);

	fd_set readfds;
    char ch;
    while (1) {
        FD_ZERO(&readfds);
        FD_SET(0,&readfds);
        FD_SET(sid, &readfds);
        int ready = select(sid+1, &readfds, NULL,NULL,NULL);
        if (ready) {
                if (FD_ISSET(0,&readfds)) {
					int rc = read(0,&ch,1);
					if (!rc) exit(1);
		            send(sid, &ch, 1,0);
				} else if (FD_ISSET(sid,&readfds)) { // if there are data in sid
					int rc = read(sid,&ch,1);
					if (rc > 0) {
						printf("%c", ch);
					}
					else {
						fprintf(stderr, "exiting remote shell\n");
						close(sid);
						exit(-2);
					}
				}

			}
	}
}