/*****************************************************************************/ /* Simple TCP client */ /* */ /* The client get the following input: */ /* * Address / name of the host which runs the server */ /* */ /* */ /* Process: */ /* The clients resolves server name (no resolution is needed for address) */ /* Conenction with the server */ /* Passing the message to the server */ /* */ /* Termination: */ /* Close the connection as needed */ /* */ /* */ /* */ /* The source is taken from Beej's Guide to Network Programming */ /* */ /* */ /* */ /*****************************************************************************/ void signal_pipe(int signo); #include <stdio.h> #include <stdlib.h> #include <errno.h> #include <string.h> #include <netdb.h> #include <sys/types.h> #include <netinet/in.h> #include <sys/socket.h> #include <signal.h> #define PORT 3490 /* the port client will be connecting to */ #define MAXDATASIZE 100 /* max number of bytes we can get at once */ int main(int argc, char *argv[]) { int sockfd, numbytes; /*Socket file descriptor & bystes sent */ char buf[MAXDATASIZE]; /*The string to be passed */ struct hostent *he; /*Is needed for address resolution */ struct sockaddr_in their_addr; /* connector's address information */ if (argc != 2) { /*If not enaugh parameters were passed */ fprintf(stderr,"usage: client hostname\n"); exit(1); } if ((he=gethostbyname(argv[1])) == NULL) { /* Host name resolution */ herror("gethostbyname"); exit(1); } if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) { /*Define the Internet socket,TCP*/ perror("socket"); exit(1); } their_addr.sin_family = AF_INET; /*Host byte order */ their_addr.sin_port = htons(PORT); /*Short, network byte order */ their_addr.sin_addr = *((struct in_addr *)he->h_addr); /*Assign address of the server */ bzero(&(their_addr.sin_zero), 8); /*Zero the rest of the struct */ /*Connecting the server */ signal (SIGPIPE, signal_pipe); if (connect(sockfd, (struct sockaddr *)&their_addr, \ sizeof(struct sockaddr)) == -1) { perror("connect"); exit(1); } while(1){ if ((numbytes=recv(sockfd, buf, MAXDATASIZE, 0)) == -1) {/*Recieve infor from the server*/ perror("recv"); exit(1); } buf[numbytes] = '\0'; /*The info from the server has no \0 at the end of string */ printf("Received: %s",buf); if (send(sockfd, "Hello-client!\n", 14, 0) == -1){ perror("send"); exit(0); } } close(sockfd); return 0; } void signal_pipe(int signo) { printf("INTERUPT signal - SIGPIPE\n"); return; }