memchr, memrchr, rawmemchr - scan memory for a character
void *memchr(const void *s, int c, size_t n);
void *memrchr(const void *s, int c, size_t n);
void *rawmemchr(const void *s, int c);
Feature Test Macro Requirements for glibc (see feature_test_macros
() function scans the initial n
bytes of the memory area
pointed to by s
for the first instance of c
. Both c
the bytes of the memory area pointed to by s
are interpreted as
() function is like the memchr
() function, except that
it searches backward from the end of the n
bytes pointed to by s
instead of forward from the beginning.
() function is similar to memchr
(): it assumes (i.e.,
the programmer knows for certain) that an instance of c
in the memory area starting at the location pointed to by s
, and so
performs an optimized search for c
(i.e., no use of a count argument to
limit the range of the search). If an instance of c
is not found, the
results are unpredictable. The following call is a fast means of locating a
string's terminating null byte:
char *p = rawmemchr(s, '\0');
() and memrchr
() functions return a pointer to the
matching byte or NULL if the character does not occur in the given memory
() function returns a pointer to the matching byte, if one
is found. If no matching byte is found, the result is unspecified.
() first appeared in glibc in version 2.1.
() first appeared in glibc in version 2.2.
For an explanation of the terms used in this section, see attributes
|memchr (), memrchr (), rawmemchr ()
(): POSIX.1-2001, POSIX.1-2008, C89, C99, SVr4, 4.3BSD.
() function is a GNU extension, available since glibc 2.1.91.
() function is a GNU extension, available since glibc 2.1.