endwin() doesn't work in pthread cleanup function

[Mike]

The following piece of code can't reset the shell after it terminates. 
Once endwin is moved to main(), it works.



#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif

#include <curses.h>
#include <pthread.h>
#include <signal.h>
#include <stdlib.h>

void cleanup_win(void *data)
{
 endwin();
 return;
}

void *thread1(void *data)
{
 char             buf[256];
 int             old_state, i=0;

 pthread_detach(pthread_self());
 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &old_state);
 pthread_cleanup_push(cleanup_win, NULL);

 (void) initscr();        /* Initialize the curses library.  */
 cbreak();
 echo();

 while (1) {
   mvprintw(0, 0, "i=%d", i);
   refresh();
   sleep(1);            /* Sleep 1 seconds.  */
 }

 pthread_cleanup_pop(1);
 pthread_setcancelstate(old_state, NULL);
 return NULL;
}

sighandler_t     old_sighandler;

int main(int argc, char *argv[])
{
 pthread_t         thread_id;
 int             c;

 /* Ignore signal to avoid terminating thread1.  */
 old_sighandler = signal(SIGINT, SIG_IGN);
 if (old_sighandler == SIG_ERR) {
   perror("signal() error");
   exit(1);
 }

 pthread_create(&thread_id, NULL, thread1, NULL);
 while (1) {
   c = getc(stdin);        /* Press any key to terminate thread1.  */
   if (c != EOF) {
     pthread_cancel(thread_id);
     signal(SIGINT, old_sighandler);
     break;
   }
 }

 exit(0);
}