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.
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 contents of the message strings returned by strsignal() should be
determined by the setting of the LC_MESSAGES category in the current
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.
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.
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information
Technology -- Portable Operating System Interface (POSIX), The Open
Group Base Specifications Issue 7, Copyright (C) 2013 by the
Institute of Electrical and Electronics Engineers, Inc and The Open
Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
applied.) In the event of any discrepancy between this version and
the original IEEE and The Open Group Standard, the original IEEE and
The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the
source files to man page format. To report such errors, see
IEEE/The Open Group 2013 STRSIGNAL(3P)