diff options
Diffstat (limited to 'sysdeps/generic/utmp_file.c')
| -rw-r--r-- | sysdeps/generic/utmp_file.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/sysdeps/generic/utmp_file.c b/sysdeps/generic/utmp_file.c index 0baf4118e9..d2a2b33ce0 100644 --- a/sysdeps/generic/utmp_file.c +++ b/sysdeps/generic/utmp_file.c @@ -74,9 +74,16 @@ static void timeout_handler (int signum) {}; fl.l_type = F_UNLCK; \ __fcntl ((fd), F_SETLKW, &fl); \ \ - /* Reset the signal handler and alarm. */ \ + /* Reset the signal handler and alarm. We must reset the alarm \ + before resetting the handler so our alarm does not generate a \ + spurious SIGALRM seen by the user. However, we cannot just set \ + the user's old alarm before restoring the handler, because then \ + it's possible our handler could catch the user alarm's SIGARLM \ + and then the user would never see the signal he expected. */ \ + alarm (0); \ __sigaction (SIGALRM, &old_action, NULL); \ - alarm (old_timeout); \ + if (old_timeout != 0) \ + alarm (old_timeout); \ } while (0) |