Iterating over a list of possible signals

Question

I have some code that I want to use to print a list of signals that prints the names of the signals in the signal mask of the calling process.

The starting code that I h

Answer 1

If you're looking for a list or array of signals, then I'm afraid that there isn't one defined in signal.h. The only thing you can do is define it yourself and iterate over it. If you want, you could define it in a different helper file so as not to pollute the actual code.

Example program:

#include "siglist.h"
#include 
#include 

int main(void) {
    sigset_t sigset;

    // ... initialize stuff ...

    for (size_t i = 0; i < SIGLIST_LENGTH; i++) {
        if (sigismember(&sigset, siglist[i].code))
            printf("%d - %s: %s.\n", siglist[i].code, siglist[i].name, siglist[i].description);
    }

    return 0;
}

File siglist.h (all those ifdef are needed since you cannot know beforehand which signals are defined and which aren't on the target machine):

#ifndef SIGLIST_H_INCLUDED
#define SIGLIST_H_INCLUDED

#include 

struct siginfo {
    int code;
    char *name;
    char *description;
};

const struct siginfo siglist[] = {
#ifdef SIGABRT
    {SIGABRT  , "SIGABRT"  , "Abort signal"},
#endif
#ifdef SIGALRM
    {SIGALRM  , "SIGALRM"  , "Timer signal"},
#endif
#ifdef SIGBUS
    {SIGBUS   , "SIGBUS"   , "Bus error (bad memory access)"},
#endif
#ifdef SIGCHLD
    {SIGCHLD  , "SIGCHLD"  , "Child stopped or terminated"},
#endif
#ifdef SIGCLD
    {SIGCLD   , "SIGCLD"   , "Child stopped or terminated"},
#endif
#ifdef SIGCONT
    {SIGCONT  , "SIGCONT"  , "Continue if stopped"},
#endif
#ifdef SIGEMT
    {SIGEMT   , "SIGEMT"   , "Emulator trap"},
#endif
#ifdef SIGFPE
    {SIGFPE   , "SIGFPE"   , "Floating-point exception"},
#endif
#ifdef SIGHUP
    {SIGHUP   , "SIGHUP"   , "Hangup detected on controlling terminal or death of controlling process"},
#endif
#ifdef SIGILL
    {SIGILL   , "SIGILL"   , "Illegal Instruction"},
#endif
#ifdef SIGINFO
    {SIGINFO  , "SIGINFO"  , "Power failure"},
#endif
#ifdef SIGINT
    {SIGINT   , "SIGINT"   , "Interrupt from keyboard"},
#endif
#ifdef SIGIO
    {SIGIO    , "SIGIO"    , "I/O now possible"},
#endif
#ifdef SIGIOT
    {SIGIOT   , "SIGIOT"   , "IOT trap: Abort signal"},
#endif
#ifdef SIGKILL
    {SIGKILL  , "SIGKILL"  , "Kill signal"},
#endif
#ifdef SIGLOST
    {SIGLOST  , "SIGLOST"  , "File lock lost "},
#endif
#ifdef SIGPIPE
    {SIGPIPE  , "SIGPIPE"  , "Broken pipe: write to pipe with no readers"},
#endif
#ifdef SIGPOLL
    {SIGPOLL  , "SIGPOLL"  , "Pollable event: I/O now possible"},
#endif
#ifdef SIGPROF
    {SIGPROF  , "SIGPROF"  , "Profiling timer expired"},
#endif
#ifdef SIGPWR
    {SIGPWR   , "SIGPWR"   , "Power failure"},
#endif
#ifdef SIGQUIT
    {SIGQUIT  , "SIGQUIT"  , "Quit from keyboard"},
#endif
#ifdef SIGSEGV
    {SIGSEGV  , "SIGSEGV"  , "Invalid memory reference"},
#endif
#ifdef SIGSTKFLT
    {SIGSTKFLT, "SIGSTKFLT", "Stack fault on coprocessor"},
#endif
#ifdef SIGSTOP
    {SIGSTOP  , "SIGSTOP"  , "Stop process"},
#endif
#ifdef SIGTSTP
    {SIGTSTP  , "SIGTSTP"  , "Stop typed at terminal"},
#endif
#ifdef SIGSYS
    {SIGSYS   , "SIGSYS"   , "Bad system call "},
#endif
#ifdef SIGTERM
    {SIGTERM  , "SIGTERM"  , "Termination signal"},
#endif
#ifdef SIGTRAP
    {SIGTRAP  , "SIGTRAP"  , "Trace/breakpoint trap"},
#endif
#ifdef SIGTTIN
    {SIGTTIN  , "SIGTTIN"  , "Terminal input for background process"},
#endif
#ifdef SIGTTOU
    {SIGTTOU  , "SIGTTOU"  , "Terminal output for background process"},
#endif
#ifdef SIGUNUSED
    {SIGUNUSED, "SIGUNUSED", "Bad system call "},
#endif
#ifdef SIGURG
    {SIGURG   , "SIGURG"   , "Urgent condition on socket "},
#endif
#ifdef SIGUSR1
    {SIGUSR1  , "SIGUSR1"  , "User-defined signal 1"},
#endif
#ifdef SIGUSR2
    {SIGUSR2  , "SIGUSR2"  , "User-defined signal 2"},
#endif
#ifdef SIGVTALRM
    {SIGVTALRM, "SIGVTALRM", "Virtual alarm clock "},
#endif
#ifdef SIGXCPU
    {SIGXCPU  , "SIGXCPU"  , "CPU time limit exceeded "},
#endif
#ifdef SIGXFSZ
    {SIGXFSZ  , "SIGXFSZ"  , "File size limit exceeded"},
#endif
#ifdef SIGWINCH
    {SIGWINCH , "SIGWINCH" , "Window resize signal"},
#endif
};

const size_t SIGLIST_LENGTH = sizeof(siglist)/sizeof(siglist[0]);

#endif // SIGLIST_H_INCLUDED