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Try for a configurable time and quit

Hi, am writing a C++ program that needs to execute a function, provided with a lib, that may hang resulting in the whole thread getting stuck. If I want to say wait for only a few seconds and then move on, is there a way to do this? Thanks.

Quote:

Originally Posted by grob115 (Post 4732760)

Hi grob115,

now that sounds like a strange library function! Why does it behave like that? Is that really within its specification?

Anyway: You could create a new thread (man pthread_create), call that weird library function in that (using your own wrapper function), and monitor how that goes from your main thread. But to me, that sounds like a lot of work for just calling a library function...

Regards
dmdeb

Some example code for that (hanger.c):

Code:

#include <assert.h>

#include <stdio.h>

#include <stdlib.h>

#include <pthread.h>

#include <unistd.h>



static int done = 0;



void obnoxious_library_function(void)

{

    if (random() % 2)

    {

        printf( "OK.\n" );

    }

    else

    {

        printf( "Hanging...\n" );

        sleep( 60 );

    }

}



void* my_wrapper(void *genarg)

{

    assert( genarg == NULL );



    done = 0;

    obnoxious_library_function( );

    done = 1;



    return NULL;

}



int main(void)

{

    for (;;)

    {

        pthread_t  thread;

        int        ret;



        ret = pthread_create( &thread, NULL, &my_wrapper, NULL );

        assert( ret == 0 );



        sleep( 1 );



        if (!done)

        {

            void  *result;



            ret = pthread_cancel( thread );

            assert( ret == 0 );



            ret = pthread_join( thread, &result );

            assert( result == PTHREAD_CANCELED );

        }

    }

}

Makefile example:

Code:

CFLAGS=-W -Wall -Werror -pedantic

LDFLAGS=-pthread

CC=gcc



all: hanger

But again: That library function behavior sounds really weird.