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@evanharmon
Created March 29, 2016 01:54
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SImple base client in C
#include <stdio.h>
#include <stdlib.h>
#include <netdb.h>
#include <netinet/in.h>
#include <string.h>
#include <unistd.h>
/* adapted from http://www.cs.rpi.edu/~moorthy/Courses/os98/Pgms/socket.html */
int main(int argc, char *argv[]) {
int sockfd, portno, n;
struct sockaddr_in serv_addr;
struct hostent *server;
char buffer[256];
if (argc < 3) {
fprintf(stderr, "usage %s hostname port\n", argv[0]);
exit(0);
}
portno = atoi(argv[2]);
/* Create a socket point */
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0) {
perror("Error opening socket");
exit(1);
}
server = gethostbyname(argv[1]);
if (server == NULL) {
fprintf(stderr, "Error, no such host\n");
exit(0);
}
bzero((char *) &serv_addr, sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
bcopy((char *) server->h_addr, (char*) &serv_addr.sin_addr.s_addr, server->h_length);
serv_addr.sin_port = htons(portno);
/* Connect to server */
if (connect(sockfd, (struct sockaddr*) &serv_addr, sizeof(serv_addr)) < 0) {
perror("Error connecting");
exit(1);
}
/* Ask for message from user, will be read on server */
printf("Please enter the message: ");
bzero(buffer, 256);
fgets(buffer, 255, stdin);
/* Send message to server */
n = write(sockfd, buffer, strlen(buffer));
if (n < 0) {
perror("Error writing to socket");
exit(1);
}
/* Read response from server */
bzero(buffer, 265);
n = read(sockfd, buffer, 255);
if (n < 0) {
perror("Error writing to socket");
exit(1);
}
printf("%s\n", buffer);
return 0;
}
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