Re: signalfd()

Muttley@DastardlyHQ.org writes:

Hi
>
I've been playing around with signalfd() on linux and it seems to work but
there also seems to be zero information other than the signal number in the
signalfd_siginfo structure returned from a read().
>
Where I'd expect PID and UID to be set as in reception of a signal handler
set using sigaction with the siginfo_t passed to the handler, the below code
returns 0 for everything in the signalfd_siginfo structure.
>
The relevant parts of the code are below. Have I done something wrong?
>
        struct signalfd_siginfo siginfo;
:
:
sigemptyset(&sigset);
        sigaddset(&sigset,SIGINT);  /* Control-C */
        sigaddset(&sigset,SIGTSTP); /* Control-Z */

[...]

sigaction(2) documents the details regarding which fields in a siginfo
structure will be set under which conditions and if were using C-c and
C-z to generate signals, the pid and uid values shouldn't be set. They
should be set when using kill(2) or sigqueue(2) to send signals.