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 and the American National Standards Committee X3, 6.\" on Information Processing Systems. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)strcmp.3 8.1 (Berkeley) 6/4/93 33.\" 34.Dd April 3, 2022 35.Dt STRCMP 3 36.Os 37.Sh NAME 38.Nm strcmp , 39.Nm strncmp 40.Nd compare strings 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.In string.h 45.Ft int 46.Fn strcmp "const char *s1" "const char *s2" 47.Ft int 48.Fn strncmp "const char *s1" "const char *s2" "size_t len" 49.Sh DESCRIPTION 50The 51.Fn strcmp 52and 53.Fn strncmp 54functions 55lexicographically compare the null-terminated strings 56.Fa s1 57and 58.Fa s2 . 59.Pp 60The 61.Fn strncmp 62function 63compares not more than 64.Fa len 65characters. 66Because 67.Fn strncmp 68is designed for comparing strings rather than binary data, 69characters that appear after a 70.Ql \e0 71character are not compared. 72.Sh RETURN VALUES 73The 74.Fn strcmp 75and 76.Fn strncmp 77functions return an integer greater than, equal to, or less than 0, according 78as the string 79.Fa s1 80is greater than, equal to, or less than the string 81.Fa s2 . 82The comparison is done using unsigned characters, so that 83.Ql \e200 84is greater than 85.Ql \e0 . 86.Sh SEE ALSO 87.Xr bcmp 3 , 88.Xr memcmp 3 , 89.Xr strcasecmp 3 , 90.Xr strcoll 3 , 91.Xr strxfrm 3 , 92.Xr wcscmp 3 93.Sh STANDARDS 94The 95.Fn strcmp 96and 97.Fn strncmp 98functions 99conform to 100.St -isoC . 101.Sh HISTORY 102The 103.Fn strcmp 104function first appeared in the Programmer's Workbench (PWB/UNIX) 105and was ported to 106.At v7 ; 107.Fn strncmp 108first appeared in 109.At v7 . 110