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.
strcat — concatenate two strings
char *strcat(char *restrict s1, const char *restrict s2);
The functionality described on this reference page is aligned with the
ISO C standard. Any conflict between the requirements described here
and the ISO C standard is unintentional. This volume of
POSIX.1‐2008 defers to the ISO C standard.
The strcat() function shall append a copy of the string
pointed to by s2 (including the terminating NUL character) to the end
of the string pointed to by s1. The initial byte of s2
overwrites the NUL character at the end of s1. If copying takes place
between objects that overlap, the behavior is undefined.
The strcat() function shall return s1; no return value is reserved
to indicate an error.
No errors are defined.
The following sections are informative.
This version is aligned with the ISO C standard; this does not affect
compatibility with XPG3 applications. Reliable error detection by this
function was never guaranteed.
The Base Definitions volume of POSIX.1‐2008,
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 .
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