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MEMMEM(3)                  Library Functions Manual                  MEMMEM(3)

NAME
     memmem - locate substring in byte string

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <string.h>

     void *
     memmem(const void *block, size_t blen, const void *pat, size_t plen);

DESCRIPTION
     The memmem() function locates the first occurrence of the binary string
     pat of size plen bytes in the byte string block of size blen bytes.

RETURN VALUES
     The memmem() function returns a pointer to the substring located, or NULL
     if no such substring exists within block.

     If plen is zero, block is returned, i.e. a zero length pat is deemed to
     match the start of the string, as with strstr(3).

SEE ALSO
     bm(3), memchr(3), strchr(3), strstr(3)

STANDARDS
     The memmem function conforms to IEEE Std 1003.1-2024 ("POSIX.1").

HISTORY
     memmem() first appeared in the Free Software Foundation's glibc library.

NetBSD 11.99                   November 1, 2024                   NetBSD 11.99