|
NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ATTRIBUTES | CONFORMING TO | NOTES | SEE ALSO | COLOPHON |
STRCASECMP(3) Linux Programmer's Manual STRCASECMP(3)
strcasecmp, strncasecmp - compare two strings ignoring case
#include <strings.h>
int strcasecmp(const char *s1, const char *s2);
int strncasecmp(const char *s1, const char *s2, size_t n);
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.
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.
For an explanation of the terms used in this section, see
attributes(7).
┌────────────────────────────┬───────────────┬────────────────┐
│Interface │ Attribute │ Value │
├────────────────────────────┼───────────────┼────────────────┤
│strcasecmp(), strncasecmp() │ Thread safety │ MT-Safe locale │
└────────────────────────────┴───────────────┴────────────────┘
4.4BSD, POSIX.1-2001, POSIX.1-2008.
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 defined.
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 unspecified.
bcmp(3), memcmp(3), strcmp(3), strcoll(3), string(3), strncmp(3),
wcscasecmp(3), wcsncasecmp(3)
This page is part of release 4.12 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the
latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
2016-07-17 STRCASECMP(3)
Pages that refer to this page: bcmp(3), memcmp(3), strcmp(3), strcoll(3), string(3), strstr(3), strverscmp(3), strxfrm(3), wcscasecmp(3), wcsncasecmp(3)