I'm trying to make a server program that uses sockets and threads. I can get it to compile, but it keeps giving me a segmentation fault. I've made a number of changes to the program, and have no idea what is causing it. If anyone has an idea, please let me know. Here's the code, followed by the output i get. (Compiled using gcc) I've gotten the client code to work with the server code before I added the threads, but not now.
output:Code:#include <sys/types.h> #include <sys/socket.h> #include <stdio.h> #include <netinet/in.h> #include <signal.h> #include <unistd.h> #include <pthread.h> void *thread_function(void *arg); int main () { int res; /* for error checking */ pthread_t client; void *thread_result; int j = 0; /* counter */ int server_sockfd, client_sockfd; int server_len, client_len; struct sockaddr_in server_address; struct sockaddr_in client_address; server_sockfd = socket(AF_INET, SOCK_STREAM, 0); server_address.sin_family = AF_INET; server_address.sin_addr.s_addr = htonl(INADDR_ANY); server_address.sin_port = htons(9734); server_len = sizeof(server_address); bind(server_sockfd, (struct sockaddr *)&server_address, server_len); listen(server_sockfd, 5); signal(SIGCHLD, SIG_IGN); while(1) { client_len = sizeof(client_address); client_sockfd = accept(server_sockfd, (struct sockaddr *)&client_address, &client_len); printf("client_sockfd after accept call: %d\n", client_sockfd); if(client_sockfd < 0) { perror("server: accept error"); exit(1); } printf("fixin to create pthread\n"); res = pthread_create(&client, NULL, thread_function, (void *) client_sockfd); if(res != 0) { perror("Thread creation failed"); exit(1); } printf("pthread created\n"); res = pthread_join(client, &thread_result); printf("pthread joined?\n"); if(res != 0) { perror("Thread join failed"); exit(1); } printf("pthread joined.\n"); } } void *thread_function(void *arg) { char ch; int sockfd; printf("inside thread_function\n"); sockfd = *((int *)arg); printf("client_sockfd assigned: %d\n", sockfd); read(sockfd, &ch, 1); printf("char read: %c\n", ch); sleep(1); ch++; write(sockfd, &ch, 1); printf("char sent: %c\n", ch); close(sockfd); pthread_exit(1); }
client_sockfd after accept call: 4
fixin to create pthread
inside thread_function
pthread created
char from server = z
[1]+ Segmentation fault ./server4.exe
(client code)
Code:#include<sys/types.h> #include<sys/socket.h> #include<stdio.h> #include<netinet/in.h> #include<arpa/inet.h> #include<unistd.h> int main() { int sockfd; int len; struct sockaddr_in address; int result; char ch = 'A'; sockfd = socket(AF_INET, SOCK_STREAM, 0); address.sin_family = AF_INET; address.sin_addr.s_addr = inet_addr("127.0.0.1"); address.sin_port = htons(9734); len = sizeof(address); result = connect(sockfd, (struct sockaddr *)&address, len); if(result == -1) { perror("client1"); exit(1); } write(sockfd, &ch, 1); ch = 'z'; read(sockfd, &ch, 1); printf("char from server: %c\n", ch); close(sockfd); exit(0); }



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