.\" -*- coding: UTF-8 -*- .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) .\" .\" %%%LICENSE_START(VERBATIM) .\" Permission is granted to make and distribute verbatim copies of this .\" manual provided the copyright notice and this permission notice are .\" preserved on all copies. .\" .\" Permission is granted to copy and distribute modified versions of this .\" manual under the conditions for verbatim copying, provided that the .\" entire resulting derived work is distributed under the terms of a .\" permission notice identical to this one. .\" .\" Since the Linux kernel and libraries are constantly changing, this .\" manual page may be incorrect or out-of-date. The author(s) assume no .\" responsibility for errors or omissions, or for damages resulting from .\" the use of the information contained herein. The author(s) may not .\" have taken the same level of care in the production of this manual, .\" which is licensed free of charge, as they might when working .\" professionally. .\" .\" Formatted or processed versions of this manual, if unaccompanied by .\" the source, must acknowledge the copyright and authors of this work. .\" %%%LICENSE_END .\" .\" References consulted: .\" Linux libc source code .\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) .\" 386BSD man pages .\" Modified Sat Jul 24 18:55:27 1993 by Rik Faith (faith@cs.unc.edu) .\"******************************************************************* .\" .\" This file was generated with po4a. Translate the source file. .\" .\"******************************************************************* .TH MEMCMP 3 "15 Septiembre 2017" "" "Manual del Programador de Linux" .SH NOMBRE memcmp \- compara areas de memoria .SH SINOPSIS .nf \fB#include \fP .PP \fBint memcmp(const void *\fP\fIs1\fP\fB, const void *\fP\fIs2\fP\fB, size_t \fP\fIn\fP\fB);\fP .fi .SH DESCRIPCIÓN The \fBmemcmp\fP() function compares the first \fIn\fP bytes (each interpreted as \fIunsigned char\fP) of the memory areas \fIs1\fP and \fIs2\fP. .SH "VALOR DEVUELTO" The \fBmemcmp\fP() function returns an integer less than, equal to, or greater than zero if the first \fIn\fP bytes of \fIs1\fP is found, respectively, to be less than, to match, or be greater than the first \fIn\fP bytes of \fIs2\fP. .PP For a nonzero return value, the sign is determined by the sign of the difference between the first pair of bytes (interpreted as \fIunsigned char\fP) that differ in \fIs1\fP and \fIs2\fP. .PP If \fIn\fP is zero, the return value is zero. .SH ATRIBUTOS Para obtener una explicación de los términos usados en esta sección, véase \fBattributes\fP(7). .TS allbox; lb lb lb l l l. Interfaz Atributo Valor T{ \fBmemcmp\fP() T} Seguridad del hilo Multi\-hilo seguro .TE .SH "CONFORME A" POSIX.1\-2001, POSIX.1\-2008, C89, C99, SVr4, 4.3BSD. .SH NOTAS Do not use \fBmemcmp\fP() to compare security critical data, such as cryptographic secrets, because the required CPU time depends on the number of equal bytes. Instead, a function that performs comparisons in constant time is required. Some operating systems provide such a function (e.g., NetBSD's \fBconsttime_memequal\fP()), but no such function is specified in POSIX. On Linux, it may be necessary to implement such a function oneself. .SH "VÉASE TAMBIÉN" \fBbcmp\fP(3), \fBbstring\fP(3), \fBstrcasecmp\fP(3), \fBstrcmp\fP(3), \fBstrcoll\fP(3), \fBstrncasecmp\fP(3), \fBstrncmp\fP(3), \fBwmemcmp\fP(3) .SH COLOFÓN Esta página es parte de la versión 5.10 del proyecto Linux \fIman\-pages\fP. Puede encontrar una descripción del proyecto, información sobre cómo informar errores y la última versión de esta página en \%https://www.kernel.org/doc/man\-pages/. .PP .SH TRADUCCIÓN La traducción al español de esta página del manual fue creada por Vicente Pastor Gómez y Juan Piernas . .PP Esta traducción es documentación libre; lea la .UR https://www.gnu.org/licenses/gpl-3.0.html GNU General Public License Version 3 .UE o posterior con respecto a las condiciones de copyright. No existe NINGUNA RESPONSABILIDAD. .PP Si encuentra algún error en la traducción de esta página del manual, envíe un correo electrónico a .MT debian-l10n-spanish@lists.debian.org .ME .