memcmp(3)                  Library Functions Manual                  memcmp(3)

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       <?><?><?><?><?> C (libc, -lc)

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       #include <string.h>

       int memcmp(const void s1[.n], const void s2[.n], size_t n);

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       <?><?><?><?><?><?><?> memcmp() <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?> n <?><?><?><?> (<?><?><?><?><?><?> <?><?><?>
       unsigned char) <?><?> <?><?><?><?><?><?><?><?> <?><?><?><?><?><?> s1
       <?> s2.

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       <?><?><?> <?><?><?><?> <?><?><?><?> <?><?><?><?> <?><?><?><?><?><?> n
       <?><?><?><?> <?><?> s1 <?><?><?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?>, <?><?><?><?><?>, <?><?><?> <?><?><?><?><?><?>
       <?><?><?> <?><?><?><?><?><?> n <?><?><?><?> <?><?> s2.

       <?><?><?> <?><?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?>, <?><?><?><?><?><?><?><?><?> <?><?>
       <?><?><?><?>, <?><?><?> <?><?><?><?>
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       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?> <?><?><?><?>
       <?><?><?><?><?><?> (<?><?><?><?><?><?><?> unsigned char) <?> s1 <?> s2.

       <?><?><?><?> n <?><?><?><?><?> <?><?><?><?>,
       <?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?> <?><?><?><?>.

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       <?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?> <?> attributes(7).

       +----------------------------+----------------------------------------------------------+--------------------------+
       |<?><?><?><?><?><?><?><?><?> | <?><?><?><?><?><?><?>                                    | <?><?><?><?><?><?><?><?> |
       +----------------------------+----------------------------------------------------------+--------------------------+
       |memcmp()                    | <?><?><?><?><?><?><?><?><?><?><?><?> <?> <?><?><?><?><?> | MT-Safe                  |
       +----------------------------+----------------------------------------------------------+--------------------------+
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       C11, POSIX.1-2008.

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       POSIX.1-2001, C89, SVr4, 4.3BSD.

CAVEATS
       Do not use memcmp()  to compare confidential data, such as
       cryptographic secrets, because the CPU time required for the comparison
       depends on the contents of the addresses compared, this function is
       subject to timing-based side-channel attacks.  In such cases, a
       function that performs comparisons in deterministic time, depending
       only on n (the quantity of bytes compared)  is required.  Some
       operating systems provide such a function (e.g., NetBSD's
       consttime_memequal()), but no such function is specified in POSIX.  On
       Linux, you may need to implement such a function yourself.

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       bstring(3), strcasecmp(3), strcmp(3), strcoll(3), strncasecmp(3),
       strncmp(3), wmemcmp(3)

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       <?><?><?><?><?><?><?><?><?><?>(<?>) aereiae <aereiae@gmail.com>, Alexey
       <a.chepugov@gmail.com>, Azamat Hackimov <azamat.hackimov@gmail.com>,
       Dmitriy S. Seregin <dseregin@59.ru>, Dmitry Bolkhovskikh
       <d20052005@yandex.ru>, ITriskTI <ITriskTI@gmail.com>, Max Is
       <ismax799@gmail.com>, Yuri Kozlov <yuray@komyakino.ru>, <?><?><?><?>
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       <maljanow@outlook.com>

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       <<debian-l10n-russian@lists.debian.org>>.

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                             2 <?><?><?> 2024 <?>.                   memcmp(3)