STRSTR(3P) POSIX Programmer's Manual STRSTR(3P)
PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the correspond-
ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.
NAME
strstr -- find a substring
SYNOPSIS
#include <string.h>
char *strstr(const char *s1, const char *s2);
DESCRIPTION
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 strstr() function shall locate the first occurrence in the string pointed to by s1 of the sequence of bytes (excluding the terminating
NUL character) in the string pointed to by s2.
RETURN VALUE
Upon successful completion, strstr() shall return a pointer to the located string or a null pointer if the string is not found.
If s2 points to a string with zero length, the function shall return s1.
ERRORS
No errors are defined.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
strchr()
The Base Definitions volume of POSIX.1-2008, <string.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition, Standard for Information Technol-
ogy -- 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 Stan-
dard 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 https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE
/The Open Group 2013 STRSTR(3P)