COMP1521 19T3 - Computer Systems Fundamentals
COMP1521 19T3 Forum View | Computer Systems Fundamentals tcp_client.c A simple TCP client For more explanation see: https://github.com/angrave/SystemProgramming/wiki/ #include
#include
#include
#include
#include
#include
#include
int main(void) {
// create a IPv4 TCP/IP socket
int sock_fd = socket(AF_INET, SOCK_STREAM, 0);
struct addrinfo hints = {
.ai_family = AF_INET, /* IPv4 only */
.ai_socktype = SOCK_STREAM, /* TCP */
};
// we wish to connect to port 1521 on our local machine
// first convert it to a struct addrinfo
struct addrinfo *a;
int s = getaddrinfo("localhost", "1521", &hints, &a);
if (s != 0) {
fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(s));
return 1;
}
// then try to establish a connection
if (connect(sock_fd, a->ai_addr, a->ai_addrlen) == -1) {
perror("connect");
exit(2);
}
char *message = "My name is Ingo Montoya";
printf("SENDING: %s\n", message);
write(sock_fd, message, strlen(message));
char response[1000];
int n_bytes = read(sock_fd, response, (sizeof response) - 1);
response[n_bytes] = '\0';
printf("RESPONSE WAS: %s\n", response);
close(sock_fd);
return 0;
}
tcp_server.c A simple TCP server For more explanation see: https://github.com/angrave/SystemProgramming/wiki/ #include
#include
#include
#include
#include
#include
#include
int main(int argc, char **argv) {
// create a IPv4 TCP/IP socket
int sock_fd = socket(AF_INET, SOCK_STREAM, 0);
struct addrinfo hints = {
.ai_family = AF_INET,
.ai_socktype = SOCK_STREAM,
.ai_flags = AI_PASSIVE,
};
// we wish to wait for connections on port 1521 on our local machine
// first convert it to a struct addrinfo
struct addrinfo *a;
int s = getaddrinfo(NULL, "1521", &hints, &a);
if (s != 0) {
fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(s));
exit(1);
}
// attach the address to the socket
if (bind(sock_fd, a->ai_addr, a->ai_addrlen) != 0) {
perror("bind()");
return 1;
}
// specify the maximum number of connections that can be queued for the socket
if (listen(sock_fd, 16) != 0) {
perror("listen()");
return 1;
}
printf("Waiting for connection\n");
int client_fd;
while ((client_fd = accept(sock_fd, NULL, NULL)) >= 0) {
// a real server might spawn a client process here to handle the connection
// so it can accept another connection immediately
printf("Connection made: client_fd=%d\n", client_fd);
char message[1024];
int n_bytes = read(client_fd, message, (sizeof message) - 1);
message[n_bytes] = '\0';
printf("READ %d BYTES: %s\n", n_bytes, message);
char response[1024];
snprintf(response, sizeof response, "%d bytes received \n", n_bytes);
printf("SENDING: %s\n", response);
write(client_fd, response, strlen(response));
close(client_fd);
}
close(sock_fd);
return 0;
}
web_server.c A simple Web server #include
#include
#include
#include
#include
#include
#include
int main(int argc, char **argv) {
// create a IPv4 TCP/IP socket
int sock_fd = socket(AF_INET, SOCK_STREAM, 0);
struct addrinfo hints = {
.ai_family = AF_INET,
.ai_socktype = SOCK_STREAM,
.ai_flags = AI_PASSIVE,
};
// we wish to wait for connections on port 1521 on our local machine
// first convert it to a struct addrinfo
struct addrinfo *a;
int s = getaddrinfo(NULL, "1080", &hints, &a);
if (s != 0) {
fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(s));
exit(1);
}
// attach the address to the socket
if (bind(sock_fd, a->ai_addr, a->ai_addrlen) != 0) {
perror("bind()");
return 1;
}
// specify the maximum number of connections that can be queued for the socket
if (listen(sock_fd, 16) != 0) {
perror("listen()");
return 1;
}
printf("Connect to me at http://localhost:1080/\n");
int client_fd;
while ((client_fd = accept(sock_fd, NULL, NULL)) >= 0) {
// a real server might spawn a client process here to handle the connection
// so it can accept another connection immediately
printf("Connection made: client_fd=%d\n", client_fd);
char message[1024];
int n_bytes = read(client_fd, message, (sizeof message) - 1);
message[n_bytes] = '\0';
printf("READ %d BYTES: %s\n", n_bytes, message);
printf("SENDING BACK ASCII ART\n");
char *header = "HTTP/1.1 200 OK\r\nContent-type: text/plain\r\n\r\n";
write(client_fd, header, strlen(header));
char *body = "\n |\\/\\/\\/| \n | | \n | | \n | (o)(o) \n C _) \n | ,___| \n | / \n /____\\ \n/ \\\n";
write(client_fd, body, strlen(body));
close(client_fd);
}
close(sock_fd);
return 0;
}
COMP1521 19T3: Computer Systems Fundamentals is brought to you by the School of Computer Science and Engineering at the University of New South Wales, Sydney. For all enquiries, please email the class account at cs1521@cse.unsw.edu.au CRICOS Provider 00098G
