return value in a thread

[Syntaxerr]

typedef struct
{
    int fd;
    int state;
}response_client;



void *action()
{  
    response_client resp;
    resp.fd = 2;
    resp.state = 1;
    pthread_exit(&resp);
}







int main()
{
    pthread_t t1;
    void* fd;
    void* resp;


    if(pthread_create(&t1, NULL, &action, NULL) != 0)

    {

        fprintf(stderr, "error......\n");
        exit(0);

    }else{

        printf("ok!\n");

    }

    pthread_join(t1, &resp);

    printf("test %d\n\n",*(int*)resp->state);


    return 0;

}

Hey there...

I have the problem to return the struct in the thread, i get every time after compiling:

test.c:55: error: request for member ‘state’ in something not a structure or union

I tried everything, but i dont get it to work. Can someone help me plz?

[Elysia]

First off, resp1 is not initialized. It doesn't point to anything.
Secondly, you can't dereference void pointers. If you know what type it is, then cast it to the proper type before dereferencing.
Thirdly, why do you think an integer has any members (hint: it's not a struct).

[MK27]

Thirdly, why do you think an integer has any members (hint: it's not a struct).

pthread_exit() takes a void pointer, not an int, so that part is okay. Or at least that is not what's wrong with it

[MK27]

Okay, here's an example of what you want to do:

#include  <stdio.h>
#include  <string.h>
#include  <stdlib.h>
#include  <pthread.h>

struct test {
	char str[32];
	int x;
};

void *tfunc() {
	struct test *eg = malloc(sizeof(struct test));
	strcpy(eg->str,"hello world");
	eg->x = 666;
	pthread_exit(eg);
}


int main (void) {
	pthread_t id;
	struct test *resp;

	pthread_create(&id,NULL,tfunc,NULL);
	pthread_join(id,(void**)&resp);

	printf("%s %d\n",resp->str,resp->x);

	free(resp);

	return 0;
}

Take a close look at the pointer to a pointer used in the red line, and how the struct returned must be malloc'd global memory in tfunc().

[Syntaxerr]

Thank you for your help, it works! : D

Pointer are a strange topic. In the german forum they have not responded until now.