strsignal - Man Page

get name of signal


This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.


#include <string.h>

char *strsignal(int signum);


The strsignal() function shall map the signal number in signum to an implementation-defined string and shall return a pointer to it. It shall use the same set of messages as the psignal() function.

The application shall not modify the string returned. The returned pointer might be invalidated or the string content might be overwritten by a subsequent call to strsignal() or setlocale(). The returned pointer might also be invalidated if the calling thread is terminated.

The contents of the message strings returned by strsignal() should be determined by the setting of the LC_MESSAGES category in the current locale.

The implementation shall behave as if no function defined in this standard calls strsignal().

Since no return value is reserved to indicate an error, an application wishing to check for error situations should set errno to 0, then call strsignal(), then check errno.

The strsignal() function need not be thread-safe.

Return Value

Upon successful completion, strsignal() shall return a pointer to a string. Otherwise, if signum is not a valid signal number, the return value is unspecified.


No errors are defined.

The following sections are informative.



Application Usage



If signum is not a valid signal number, some implementations return NULL, while for others the strsignal() function returns a pointer to a string containing an unspecified message denoting an unknown signal. POSIX.1-2008 leaves this return value unspecified.

Future Directions


See Also

psiginfo(), setlocale()

The Base Definitions volume of POSIX.1-2017, <string.h>

Referenced By

psiginfo(3p), setlocale(3p), string.h(0p).

2017 IEEE/The Open Group POSIX Programmer's Manual