strcasecmp(3) — Linux manual page


strcasecmp(3)           Library Functions Manual           strcasecmp(3)

NAME         top

       strcasecmp, strncasecmp - compare two strings ignoring case

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <strings.h>

       int strcasecmp(const char *s1, const char *s2);
       int strncasecmp(const char s1[.n], const char s2[.n], size_t n);

DESCRIPTION         top

       The strcasecmp() function performs a byte-by-byte comparison of
       the strings s1 and s2, ignoring the case of the characters.  It
       returns an integer less than, equal to, or greater than zero if
       s1 is found, respectively, to be less than, to match, or be
       greater than s2.

       The strncasecmp() function is similar, except that it compares no
       more than n bytes of s1 and s2.

RETURN VALUE         top

       The strcasecmp() and strncasecmp() functions return an integer
       less than, equal to, or greater than zero if s1 is, after
       ignoring case, found to be less than, to match, or be greater
       than s2, respectively.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       │ Interface                    Attribute     Value          │
       │ strcasecmp(), strncasecmp()  │ Thread safety │ MT-Safe locale │

STANDARDS         top


HISTORY         top

       4.4BSD, POSIX.1-2001.

       The strcasecmp() and strncasecmp() functions first appeared in
       4.4BSD, where they were declared in <string.h>.  Thus, for
       reasons of historical compatibility, the glibc <string.h> header
       file also declares these functions, if the _DEFAULT_SOURCE (or,
       in glibc 2.19 and earlier, _BSD_SOURCE) feature test macro is

       The POSIX.1-2008 standard says of these functions:

              When the LC_CTYPE category of the locale being used is
              from the POSIX locale, these functions shall behave as if
              the strings had been converted to lowercase and then a
              byte comparison performed.  Otherwise, the results are

SEE ALSO         top

       memcmp(3), strcmp(3), strcoll(3), string(3), strncmp(3),
       wcscasecmp(3), wcsncasecmp(3)

Linux man-pages (unreleased)     (date)                    strcasecmp(3)

Pages that refer to this page: memcmp(3)strcmp(3)strcoll(3)string(3)strstr(3)strverscmp(3)strxfrm(3)wcscasecmp(3)wcsncasecmp(3)