STRSIGNAL(3) Linux Programmer's Manual STRSIGNAL(3)

strsignal - return string describing signal

#include <string.h>
char *strsignal(int sig);
extern const char * const sys_siglist[];

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
Since glibc 2.10:
_POSIX_C_SOURCE >= 200809L
Before glibc 2.10:

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 array sys_siglist holds the signal description strings indexed by signal number. The strsignal() function should be used if possible instead of this array.

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.

For an explanation of the terms used in this section, see attributes(7).
Interface Attribute Value
strsignal () Thread safety MT-Unsafe race:strsignal locale

POSIX.1-2008. Present on Solaris and the BSDs.

psignal(3), strerror(3)
2017-09-15 GNU