Bug 113002
| Summary: | raise implemented via tkill breaks si_code | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Mike Perry <mikepery> |
| Component: | man-pages | Assignee: | Eido Inoue <havill> |
| Status: | CLOSED RAWHIDE | QA Contact: | Ben Levenson <benl> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 1 | CC: | drepper, mikepery, roland |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | i686 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | 1.66-1 | Doc Type: | Bug Fix |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2004-02-19 17:46:05 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
POSIX says that: "If the implementation supports the Threads option, the effect of the raise() function shall be equivalent to calling: pthread_kill(pthread_self(), sig);" (otherwise kill(getpid(), sig);). SI_USER's reason is written as "Signal sent by kill()." and no si_code is mentioned for pthread_kill. So I don't think POSIX mandates SI_USER in this case, but mandates that it will be the same si_code as with pthread_kill (which uses SI_TKILL as well). I concur. The standard requires that pthread_kill result in an implementation-defined value that is not equal to SI_USER or one of the other specified values. SI_TKILL is our implementation-defined value for pthread_kill. The standard further requires that raise behave as if it were a call to pthread_kill. Ergo, SI_TKILL is the correct implementation-defined value. Using SI_USER here would be in violation of the standard. Well can we get a documentation update for sigaction then? Becuase those docs only mention SI_USER, and state that it is the si_code for raise(), which is very misleading, and can lead developers to produce buggy and non-portable software (which happened to me). With linuxthreads it actually will be SI_USER, but with NPTL SI_TKILL. fixed in 1.66 (look at the man page in both the regular section vs the new POSIX section) |
From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4.1) Gecko/20031114 Galeon/1.3.10 Description of problem: It seems that raise is implemented as tkill, as evidenced by the fact that for sigaction handlers, si_code is set to SI_TKILL for raise()ed signals, when the manpages for sigaction indicate that raise should cause si_code to be set to SI_USER instead. I would think that SI_USER is the more standards correct flag to set for raise.. Version-Release number of selected component (if applicable): glibc-2.3.2-101.1 How reproducible: Always Steps to Reproduce: #include <stdio.h> #include <signal.h> void action_hdlr(int sig, siginfo_t *si, void *p) { fprintf(stderr, "%d\n", si->si_code); exit(0); } int main(int argc, char **argv) { struct sigaction sa; sa.sa_handler =0; sa.sa_flags = SA_RESTART | SA_SIGINFO; sigemptyset(&sa.sa_mask); sa.sa_sigaction = action_hdlr; sigaction(SIGILL, &sa, NULL); raise(SIGILL); } Actual Results: -6 is printed, which is the si_code for SI_TKILL, not SI_USER, as expected. Expected Results: SI_USER's value should be printed.. which is 0. Additional info: I haven't looked at the source for raise, but be wary just changing that tkill.. It may exist for threads to be able to use raise() nicely..