NAME
strcasecmp,
strcasecmp_l, strncasecmp,
strncasecmp_l —
compare strings, ignoring
case
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include
<strings.h>
int
strcasecmp(const char *s1,
const char *s2);
int
strncasecmp(const char *s1,
const char *s2, size_t n);
#include
<strings.h>
#include <xlocale.h>
int
strcasecmp_l(const char *s1,
const char *s2, locale_t
loc);
int
strncasecmp_l(const char *s1,
const char *s2, size_t n,
locale_t loc);
DESCRIPTION
The
strcasecmp()
and strncasecmp() functions compare the
null-terminated strings s1 and
s2.
The
strncasecmp()
compares at most n characters.
Although the
strcasecmp()
and strncasecmp() functions use the current locale,
the
strcasecmp_l()
and
strncasecmp_l()
functions may be passed locales directly. See
xlocale(3) for more information.
RETURN VALUES
The strcasecmp() and
strncasecmp() return an integer greater than, equal
to, or less than 0, according as s1 is
lexicographically greater than, equal to, or less than
s2 after translation of each corresponding character
to lower-case. The strings themselves are not modified. The comparison is
done using unsigned characters, so that
‘\200’ is greater than
‘\0’.
SEE ALSO
bcmp(3), memcmp(3), strcmp(3), strcoll(3), strxfrm(3), tolower(3), xlocale(3)
HISTORY
The strcasecmp() and
strncasecmp() functions first appeared in
4.4BSD. Their prototypes existed previously in
<string.h> before they were
moved to <strings.h> for
IEEE Std 1003.1-2001 (“POSIX.1”)
compliance.