When I type in to the terminal:
echo "GET /" | ./<executable name> www.google.com <port number, usually 80>
the terminal just sits there like it's waiting for input or it's stuck in an infinite loop. What is happening is that connection is taking too long I think.
/*Creating socket*/
int sock = socket(AF_INET,SOCK_STREAM, IPPROTO_TCP);
if (sock < 0) {
printf("error creating socket\n");
exit(1);
}
printf("1\n");
/*Establish connection to the echo server*/
int r = connect(sock, addrList->ai_addr, addrList->ai_addrlen);
printf("1.5\n");
if (r < 0) {
perror("Connection failed\n");
exit(1);
}
printf("2\n");
Here, the 1 prints out, but the 1.5 right after the connect doesn't print out and the terminal just sits.
This problem didn't happen before and I used to get the page's source code back instantly. But now this problem is occurring.
It started occurring after I typed in to the terminal: netstat -an -A inet | grep :2525
netstat -an -A inet | grep :2525
so this may have had an effect.
Here is the entire code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
int main(int argc, char *argv[]) {
if (argc != 3) {
printf("Invalid arguments\n");
exit(1);
}
char *serverIP = argv[1]; /*Server hostname*/
char *portNumber = argv[2]; /*Port Number*/
void *numericAddress;
char addrBuffer[INET6_ADDRSTRLEN];
in_port_t port;
char buffer_stdin[65535];
char buffer_stdout[65535];
int bytes_read = 0;
int bytes_written = 0;
/*getting integral number of string representation of port number*/
in_port_t servPort = atoi(argv[2]);
/*------------------get binary number of hostname-----------------*/
struct addrinfo addrCriteria;
memset(&addrCriteria, 0, sizeof(addrCriteria));
addrCriteria.ai_family = AF_INET;
addrCriteria.ai_socktype = SOCK_STREAM;
addrCriteria.ai_protocol = IPPROTO_TCP;
struct addrinfo *addrList;
int rtnVal = getaddrinfo(serverIP, portNumber, &addrCriteria, &addrList);
if (rtnVal != 0) {
printf("getaddrinfo() failed\n");
exit(1);
}
numericAddress = &((struct sockaddr_in *) (addrList->ai_addr))->sin_addr;
/*Converting port to binary*/
((struct sockaddr_in *)(addrList->ai_addr))->sin_port = htonl(servPort);
/*----------------------------------------------------------------*/
inet_ntop(addrList->ai_addr->sa_family, numericAddress, addrBuffer, sizeof(addrBuffer));
printf("IP ADDRESS: %s\n", addrBuffer);
/*Creating socket*/
int sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (sock < 0) {
printf("error creating socket\n");
exit(1);
}
/*printf("1\n");*/
/*Establish connection to the echo server*/
int r = connect(sock, addrList->ai_addr, addrList->ai_addrlen);
printf("%d\n", r);
if (r < 0) {
perror("Connection failed\n");
exit(1);
}
printf("2\n");
/*Reading from stdin and writing to socket until stdin ends
bytes_read = read(0, buffer_stdin, sizeof(buffer_stdin));
write(sock, buffer_stdin, bytes_read);*/
while ((bytes_read = read(0, buffer_stdin, sizeof(buffer_stdin)-1)) > 0) {
write(sock, buffer_stdin, bytes_read);
}
/*Shutting down write end of socket*/
int r_shutdown = shutdown(sock, SHUT_WR);
if (r_shutdown < 0) {
printf("Shutting down write end of socket failed\n");
exit(1);
}
/*Reading from socket and writing to stdout until socket ends*/
while ((bytes_read = read(sock, buffer_stdout, sizeof(buffer_stdout)-1)) > 0) {
write(1, buffer_stdout, bytes_read);
}
close(sock);
exit(0);
}
The correct way to do it is :
struct sockaddr_in address;
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if(sockfd!=-1)
{
perror("socket :");
printf("sockfd = %d\n", sockfd);
}
else
{
perror("socket");
exit(EXIT_FAILURE);
}
address.sin_family = AF_INET;
address.sin_addr.s_addr = inet_addr("127.0.0.1");
address.sin_port = htons(9734);
len = sizeof(struct sockaddr_in);
result = connect(sockfd, (struct sockaddr *)&address, len);
Nvm I figured it out.
Apparently I had to take into account big endian vs little endian, and so in this line:
((struct sockaddr_in *)(addrList->ai_addr))->sin_port = htonl(servPort);
the htonl should've been htons, so:
((struct sockaddr_in *)(addrList->ai_addr))->sin_port = htons(servPort);
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