MEMMEM (3)
locate a substring
SYNOPSIS
#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. Since libc 5.0.9 is still widely used, this is a
dangerous function to use.
Both old and new libc's have the bug that if needle is empty
haystack-1 (instead of haystack) is returned.
And glibc (2.0.5) makes it worse, and returns a pointer to the
last byte of `haystack'.
Hopefully this will be fixed. For the time being, memmem()
should not be used with an empty `needle'.
SEE ALSO
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