multithreading - C: pthread failing to listen, bind, and accept on a socket -

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i trying create process listen connections on socket. seems work when bind, listen, , wait accepts in main() function. when attempt create new thread , bind, listen, , accept on new thread, fails. here code.

void request_handler(int clientsock) {     file *requestedfile = null;     long filesize = 0;     struct stat st;     long bytesread;     char buffer[1024];      requestedfile = fopen("/path/book.txt", "rb");      while(!feof(requestedfile)) {         bytesread = fread(buffer, 1, sizeof(buffer), requestedfile);         send(clientsock, buffer, bytesread, 0);     }  }  void listener() {     int server_sock_desc;     struct sockaddr_in name;      int client_sock_desc;     struct sockaddr_in client_name;     socklen_t addr_size;      pthread_t handler_thread;      printf("waiting");      //connection setup     server_sock_desc = socket(pf_inet, sock_stream, 0);       if(server_sock_desc != -1) {         memset(&name, 0, sizeof(name));         name.sin_family = af_inet;         name.sin_port = htons(5000);         name.sin_addr.s_addr = htonl(inaddr_any);         int bind_result = bind(server_sock_desc, (struct sockaddr *) &name, sizeof(name));         if(bind_result == 0) {             if(listen(server_sock_desc, backlog) < 0) {                 perror("listen failed");             }              addr_size = sizeof(client_name);              //server loop continue run listening clients connecting server             while(1) {                  //new client attempting connect server                  client_sock_desc = accept(server_sock_desc, (struct sockaddr *) &client_name, &addr_size);                 if(client_sock_desc == -1) {                     if(errno == eintr) {                         continue;                     }                     else {                         perror("accept failed");                         exit(1);                     }                 }                  //connection starts here                  //create thread new clients request handled                 if(pthread_create(&handler_thread, null, request_handler, client_sock_desc) != 0) {                     perror("pthread_create failed");                 }             }         }         else {             perror("bind failed");         }     }     else {         perror("socket failed");     }  }  int main(int argc, const char * argv[]) {     pthread_t listenerthread;      if(pthread_create(&listenerthread, null,listener, null) != 0) {         perror("listener thread create failed");     } }

the weird thing is, when try run through debugger, part of listener() execute, stop out of nowhere.

you need give thread chance run. program terminates (by returning main) right after creating thread!

if want initial thread terminate , leave other thread running, call pthread_exit rather returning main. if want thread wait until listening thread terminates, call pthread_join on listening thread.

you let initial thread run off edge of map. there dragons.


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