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.Dd May 29, 2014 31.Dt STRCASECMP 3 32.Os 33.Sh NAME 34.Nm strcasecmp , 35.Nm strncasecmp 36.Nd compare strings, ignoring case 37.Sh LIBRARY 38.Lb libc 39.Sh SYNOPSIS 40.In strings.h 41.Ft int 42.Fn strcasecmp "const char *s1" "const char *s2" 43.Ft int 44.Fn strncasecmp "const char *s1" "const char *s2" "size_t len" 45.In strings.h 46.In xlocale.h 47.Ft int 48.Fn strcasecmp_l "const char *s1" "const char *s2" "locale_t loc" 49.Ft int 50.Fn strncasecmp_l "const char *s1" "const char *s2" "size_t len" "locale_t loc" 51.Sh DESCRIPTION 52The 53.Fn strcasecmp 54and 55.Fn strncasecmp 56functions 57compare the null-terminated strings 58.Fa s1 59and 60.Fa s2 . 61.Pp 62The 63.Fn strncasecmp 64function compares at most 65.Fa len 66characters. 67The 68.Fn strcasecmp_l 69and 70.Fn strncasecmp_l 71functions do the same as their non-locale versions above, but take an 72explicit locale rather than using the current locale. 73.Sh RETURN VALUES 74The functions 75.Fn strcasecmp 76and 77.Fn strncasecmp 78return an integer greater than, equal to, or less than 0, 79depending on whether 80.Fa s1 81is lexicographically greater than, equal to, or less than 82.Fa s2 83after translation of each corresponding character to lower-case. 84The strings themselves are not modified. 85The comparison is done using unsigned characters, so that 86.Sq Li \e200 87is greater than 88.Ql \e0 . 89The functions 90.Fn strcasecmp_l 91and 92.Fn strncasecmp_l 93do the same but take explicit locales. 94.Sh SEE ALSO 95.Xr bcmp 3 , 96.Xr memcmp 3 , 97.Xr strcmp 3 , 98.Xr strcoll 3 , 99.Xr strxfrm 3 , 100.Xr tolower 3 , 101.Xr wcscasecmp 3 102.Sh HISTORY 103The 104.Fn strcasecmp 105and 106.Fn strncasecmp 107functions first appeared in 108.Bx 4.4 . 109Their prototypes existed previously in 110.In string.h 111before they were moved to 112.In strings.h 113for 114.St -p1003.1-2001 115compliance. 116