client1.c

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <unistd.h>     /* used for read and write sys call */
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>

#define MAXX 10000      /* to generate rand numbers betwen 0 to 9999 */
#define TAM 125         /* size of rand vector */

/*-----------------------------Functions to convert integer to string----------------*/
size_t strlen(const char *string) {
	const char *s;
	s = string;
	while (*s)
		s++;
	return s - string;
}
char *strrev(char *str) {
	char *p1, *p2;
	if (!str || !*str)
		return str;
	for (p1 = str, p2 = str + strlen(str) - 1; p2 > p1; ++p1, --p2) {
		*p1 ^= *p2;
		*p2 ^= *p1;
		*p1 ^= *p2;
	}
	return str;
}
char *itoa(int n, char *s, int b) {
	static char digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
	int i=0, sign;
	    
	if ((sign = n) < 0)
		n = -n;
	do {
		s[i++] = digits[n % b];
	} while ((n /= b) > 0);
	if (sign < 0)
		s[i++] = '-';
	s[i] = '\0';
	return strrev(s);
}
/*------------------------------------END------------------------------------------*/

/*
* sequence of socket connection for client
* int socket(int domain, int type, int protocol);
* int connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen);
* ssize_t read(int fd, void *buf, size_t count);
* ssize_t write(int fd, const void *buf, size_t count);  
*/

int main(void){
       char *v[TAM];                           /* rand vector to future sort */
       int i, sockfd, port_number;             /* index; file descriptor; port number of connection */
       char *host;                             /* name of server host */
       struct sockaddr_in serv_addr;   	/* structure containing an internet address */
       struct hostent *server;         	/* defines a host computer on the Internet */
       int n;					/* if read and write OK */
				
       port_number = 57531;    /* port communication */
       host = "venon";         /* host who client 1 will communicate */

       sockfd = socket(AF_INET, SOCK_STREAM, 0);       /* socket communication using Internet */
       if (sockfd < 0) {
		error("ERROR opening socket");
		exit(1);
       }

       server = gethostbyname(host);   /* return a pointer to host of a line in the network host data base */
       if (server == NULL) {
              fprintf(stderr,"ERROR, no such host\n");
              exit(0);
        }

      	serv_addr.sin_family = AF_INET; /* family must be AF_INET */
      	bcopy((char *)server->h_addr, (char *)&serv_addr.sin_addr.s_addr, server->h_length); /* copies length bytes from arg1 to arg2 */
     	serv_addr.sin_port = htons(port_number); /* converts a port number in host byte order to a port number in network byte order */       
      	if (connect(sockfd,(struct sockaddr *) &serv_addr,sizeof(serv_addr)) < 0)       /* establish a connection to the server */
              error("ERROR connecting");

       srand(time(NULL));
       for (i=0; i<TAM; i++) {   
		v[i] = (char *) malloc (sizeof(char));
		bzero(v[i],5);
		itoa(rand()%MAXX,v[i],5);	/* rand number between 0 to 9999 */       

		n = write(sockfd,v[i],5);	/* write vector at the socket */
        	if (n < 0)    
			error("Error writing to socket");
 	}

       close(sockfd);
       return 0;
}