функция кодирования (CRYPT) (encoding function (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)
encrypt — encoding function (CRYPT)
Синопсис (Synopsis)
#include <unistd.h>
void encrypt(char block[64], int edflag);
Описание (Description)
The encrypt() function shall provide access to an implementation-
defined encoding algorithm. The key generated by setkey() is used
to encrypt the string block with encrypt().
The block argument to encrypt() shall be an array of length 64
bytes containing only the bytes with values of 0 and 1. The array
is modified in place to a similar array using the key set by
setkey(). If edflag is 0, the argument is encoded. If edflag is
1, the argument may be decoded (see the APPLICATION USAGE
section); if the argument is not decoded, errno shall be set to
[ENOSYS].
The encrypt() 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 encrypt(). If errno is non-
zero on return, an error has occurred.
The encrypt() function need not be thread-safe.
Возвращаемое значение (Return value)
The encrypt() function shall not return a value.
Ошибки (Error)
The encrypt() 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)
Historical implementations of the encrypt() function used a
rather primitive encoding algorithm.
In some environments, decoding might not be implemented. This is
related to some Government restrictions 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), setkey(3p)
The Base Definitions volume of POSIX.1‐2017, unistd.h(0p)
