Bug 22758

On receipt of a SIGALRM, select will return 0 when linked to the 
reentrant C library libc_r (for pthreads) and not set errno to EINTR.
When linked to libc (no pthreads) select returns -1 and sets errno
to EINTR.

How-To-Repeat: /*
 * testsel.c
 * On receipt of SIGALRM, select() returns:
 *      0 when linked with libc_r
 *      -1 otherwise.
 *
 * Tp compile with threads...
 * cc -o testsel testsel.c -pthread
 *
 * To compile without threads...
 * cc -o testsel testsel.c 
 */
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <signal.h>
#include <string.h>
#include <unistd.h>

handle_sigalarm(void)
{
  fprintf(stderr,"ALARM!\n");
}

int
main(void)
{
  struct sigaction sact;
  fd_set fds;
  int error;

  sact.sa_flags   = 1;
  sact.sa_handler = (sig_t) handle_sigalarm;
  sigaction(SIGALRM, &sact, NULL);

  FD_ZERO(&fds);
  alarm(1);

  fprintf(stderr, "test: calling select...\n");
  error = select(0, &fds, 0, 0, 0);

  fprintf(stderr, "test: select returned %d\n", error); 
  if (errno == EINTR)
    fprintf(stderr, "test: errno=EINTR\n");
  else
    fprintf(stderr, "test: errno!=EINTR (error: %s)\n", strerror(errno));
}