strsignal - Man Page

return string describing signal


Standard C library (libc, -lc)


#include <string.h>

char *strsignal(int sig);
const char *sigdescr_np(int sig);
const char *sigabbrev_np(int sig);

[[deprecated]] extern const char *const sys_siglist[];

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

sigabbrev_np(), sigdescr_np():



    From glibc 2.10 to glibc 2.31:
        _POSIX_C_SOURCE >= 200809L
    Before glibc 2.10:


    Since glibc 2.19:
    Glibc 2.19 and earlier:


The strsignal() function returns a string describing the signal number passed in the argument sig. The string can be used only until the next call to strsignal(). The string returned by strsignal() is localized according to the LC_MESSAGES category in the current locale.

The sigdescr_np() function returns a string describing the signal number passed in the argument sig. Unlike strsignal() this string is not influenced by the current locale.

The sigabbrev_np() function returns the abbreviated name of the signal, sig. For example, given the value SIGINT, it returns the string "INT".

The (deprecated) array sys_siglist holds the signal description strings indexed by signal number. The strsignal() or the sigdescr_np() function should be used instead of this array; see also Versions.

Return Value

The strsignal() function returns the appropriate description string, or an unknown signal message if the signal number is invalid. On some systems (but not on Linux), NULL may instead be returned for an invalid signal number.

The sigdescr_np() and sigabbrev_np() functions return the appropriate description string. The returned string is statically allocated and valid for the lifetime of the program. These functions return NULL for an invalid signal number.


sigdescr_np() and sigabbrev_np() first appeared in glibc 2.32.

Starting with glibc 2.32, the sys_siglist symbol is no longer exported by glibc.


For an explanation of the terms used in this section, see attributes(7).

strsignal()Thread safetyMT-Unsafe race:strsignal locale
sigdescr_np(), sigabbrev_np()Thread safetyMT-Safe


strsignal(): POSIX.1-2008. Present on Solaris and the BSDs.

sigdescr_np() and sigabbrev_np() are GNU extensions.

sys_siglist is nonstandard, but present on many other systems.


sigdescr_np() and sigabbrev_np() are thread-safe and async-signal-safe.

See Also

psignal(3), strerror(3)

Referenced By

psignal(3), signal(7), strerror(3).

The man pages sigabbrev_np(3), sigdescr_np(3) and sys_siglist(3) are aliases of strsignal(3).

2022-12-15 Linux man-pages 6.02