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memmem(3) [v7 man page]

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

NAME
memmem - locate a substring SYNOPSIS
#define _GNU_SOURCE /* See feature_test_macros(7) */ #include <string.h> void *memmem(const void *haystack, size_t haystacklen, const void *needle, size_t needlelen); DESCRIPTION
The memmem() function finds the start of the first occurrence of the substring needle of length needlelen in the memory area haystack of length haystacklen. RETURN VALUE
The memmem() function returns a pointer to the beginning of the substring, or NULL if the substring is not found. ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7). +----------+---------------+---------+ |Interface | Attribute | Value | +----------+---------------+---------+ |memmem() | Thread safety | MT-Safe | +----------+---------------+---------+ CONFORMING TO
This function is not specified in POSIX.1, but is present on a number of other systems. BUGS
In glibc 2.0, if needle is empty, memmem() returns a pointer to the last byte of haystack. This is fixed in glibc 2.1. SEE ALSO
bstring(3), strstr(3) COLOPHON
This page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/. GNU
2017-03-13 MEMMEM(3)

Check Out this Related Man Page

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

NAME
memmem - locate a substring SYNOPSIS
#define _GNU_SOURCE #include <string.h> void *memmem(const void *haystack, size_t haystacklen, const void *needle, size_t needlelen); DESCRIPTION
The memmem() function finds the start of the first occurrence of the substring needle of length needlelen in the memory area haystack of length haystacklen. RETURN VALUE
The memmem() function returns a pointer to the beginning of the substring, or NULL if the substring is not found. CONFORMING TO
This function is a GNU extension. BUGS
This function was broken in Linux libraries up to and including libc 5.0.9; there the needle and haystack arguments were interchanged, and a pointer to the end of the first occurrence of needle was returned. Both old and new libc's have the bug that if needle is empty, haystack-1 (instead of haystack) is returned. And glibc 2.0 makes it worse, returning a pointer to the last byte of haystack. This is fixed in glibc 2.1. SEE ALSO
strstr(3), feature_test_macros(7) COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. GNU
2008-12-05 MEMMEM(3)
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