how to set thread timeout time

  I wanted to download a file from Internet while I find the wget may stuck when the network is not good enough .

"wget" command  accepts -T / --timeout , however, it doesn't work right as I tried .

 

  So  I create a thread to handle this job , using pthread_cond_timedwait .

  the following program run like this : main thread create a sub_thread call thread_download in order to handle the job of download a file .  If thread_download finished in time ,it signal the main thread to stop waiting and continue somes tasks. If not, (While time's up,) it cancel the thread_download.

 

 

 

#include <stdio.h> 

#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <pthread.h>
#include <time.h>
#include <sys/time.h>

pthread_mutex_t count_lock = PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t count_cond = PTHREAD_COND_INITIALIZER;
unsigned int count = 0;

/*if it = 1 then it means download job finished in time*/

void *thread_download(void *arg)
{
    
    system("wget ftp://192.168.100.3:22/ftpdir/1.rmvb -O 1.rmvb ");
    count += 1;
    pthread_mutex_lock(&count_lock);
    pthread_cond_signal(&count_cond);
    pthread_mutex_unlock(&count_lock);
    
    pthread_exit(NULL);
}

int main(int argc, char *argv[])
{
    struct timespec m_time;
    pthread_t reader2;
    int res = 0;
    int msec; /*time out millionsec  */

pasting

    if (argc < 2) exit(1);
    msec = atoi(argv[1]);
    
    pthread_create(&reader2, NULL, thread_download, NULL);

    /* get the current time */ 
    struct timeval now; 
    gettimeofday(&now, NULL); 
    
    /* add the offset to get timeout value */ 
    m_time.tv_nsec = now.tv_usec * 1000 + (msec % 1000) * 1000000; 
    m_time.tv_sec = now.tv_sec + msec / 1000;


    pthread_mutex_lock(&count_lock);
    while(count == 0 && res != ETIMEDOUT)
        res = pthread_cond_timedwait(&count_cond, &count_lock, (const struct timespec *)&m_time);
    
    pthread_mutex_unlock(&count_lock);
    printf("res:%d\n", res);
   
   if(res==ETIMEDOUT)
   {
        printf("\n\n********* timeout **********\n\n");
//    if (pthread_kill(reader2,0)!=0)
    {
        printf("\n********* pthread_cancel **********\n");
        pthread_cancel(reader2);
    }
   }
   else
   {
        printf(" finish in time ,res = %d, count =%d\n", res , count);
   }

    pthread_join(reader2, NULL);
    return 0;
}