open STDOUT, ">&SOCK_WRITE" or die "STDOUT: $!\n";
warn "fileno(STDOUT)=",fileno(STDOUT),"\n";

##</code><code>##

fileno(STDOUT)=3

##</code><code>##

exec('perl','-e','$|=1; while(1) { sleep(5); print q:The time is now :,time,qq:\n:; };')
  or die "exec error: $!\n";