1.\" Copyright (c) 1990, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Chris Torek. 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" @(#)strcasecmp.3 8.1 (Berkeley) 6/9/93 31.\" $FreeBSD: head/lib/libc/string/strcasecmp.3 251069 2013-05-28 20:57:40Z emaste $ 32.\" 33.Dd June 9, 1993 34.Dt STRCASECMP 3 35.Os 36.Sh NAME 37.Nm strcasecmp , 38.Nm strncasecmp 39.Nd compare strings, ignoring case 40.Sh LIBRARY 41.Lb libc 42.Sh SYNOPSIS 43.In strings.h 44.Ft int 45.Fn strcasecmp "const char *s1" "const char *s2" 46.Ft int 47.Fn strncasecmp "const char *s1" "const char *s2" "size_t len" 48.In string.h 49.In xlocale.h 50.Ft int 51.Fn strcasecmp_l "const char *s1" "const char *s2" "locale_t loc" 52.Ft int 53.Fn strncasecmp_l "const char *s1" "const char *s2" "size_t len" "locale_t loc" 54.Sh DESCRIPTION 55The 56.Fn strcasecmp 57and 58.Fn strncasecmp 59functions 60compare the null-terminated strings 61.Fa s1 62and 63.Fa s2 . 64.Pp 65The 66.Fn strncasecmp 67function compares at most 68.Fa len 69characters. 70The 71.Fn strcasecmp_l 72and 73.Fn strncasecmp_l 74functions do the same as their non-locale versions above, but take an 75explicit locale rather than using the current locale. 76.Sh RETURN VALUES 77The functions 78.Fn strcasecmp 79and 80.Fn strncasecmp 81return an integer greater than, equal to, or less than 0, 82depending on whether 83.Fa s1 84is lexicographically greater than, equal to, or less than 85.Fa s2 86after translation of each corresponding character to lower-case. 87The strings themselves are not modified. 88The comparison is done using unsigned characters, so that 89.Sq Li \e200 90is greater than 91.Ql \e0 . 92The functions 93.Fn strcasecmp_l 94and 95.Fn strncasecmp_l 96do the same but take explicit locales. 97.Sh SEE ALSO 98.Xr bcmp 3 , 99.Xr memcmp 3 , 100.Xr strcmp 3 , 101.Xr strcoll 3 , 102.Xr strxfrm 3 , 103.Xr tolower 3 , 104.Xr wcscasecmp 3 105.Sh HISTORY 106The 107.Fn strcasecmp 108and 109.Fn strncasecmp 110functions first appeared in 111.Bx 4.4 . 112Their prototypes existed previously in 113.In string.h 114before they were moved to 115.In strings.h 116for 117.St -p1003.1-2001 118compliance. 119