установить ключ кодировки (CRYPT) (set encoding key (CRYPT))
Пролог (Prolog)
This manual page is part of the POSIX Programmer's Manual. The
Linux implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
Имя (Name)
setkey — set encoding key (CRYPT)
Синопсис (Synopsis)
#include <stdlib.h>
void setkey(const char *key);
Описание (Description)
The setkey() function provides access to an implementation-
defined encoding algorithm. The argument of setkey() is an array
of length 64 bytes containing only the bytes with numerical value
of 0 and 1. If this string is divided into groups of 8, the low-
order bit in each group is ignored; this gives a 56-bit key which
is used by the algorithm. This is the key that shall be used with
the algorithm to encode a string block passed to encrypt().
The setkey() function shall not change the setting of errno if
successful. An application wishing to check for error situations
should set errno to 0 before calling setkey(). If errno is non-
zero on return, an error has occurred.
The setkey() function need not be thread-safe.
Возвращаемое значение (Return value)
No values are returned.
Ошибки (Error)
The setkey() function shall fail if:
ENOSYS The functionality is not supported on this implementation.
The following sections are informative.
Примеры (Examples)
None.
Использование в приложениях (Application usage)
Decoding need not be implemented in all environments. This is
related to government restrictions in some countries on
encryption and decryption routines. Historical practice has been
to ship a different version of the encryption library without the
decryption feature in the routines supplied. Thus the exported
version of encrypt() does encoding but not decoding.
Обоснование (Rationale)
None.
Будущие направления (Future directions)
A future version of the standard may mark this interface as
obsolete or remove it altogether.
Смотри также (See also)
crypt(3p), encrypt(3p)
The Base Definitions volume of POSIX.1‐2017, stdlib.h(0p)
