setkey(3p) — Linux manual page


SETKEY(3P)              POSIX Programmer's Manual             SETKEY(3P)

PROLOG         top

       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.

NAME         top

       setkey — set encoding key (CRYPT)

SYNOPSIS         top

       #include <stdlib.h>

       void setkey(const char *key);

DESCRIPTION         top

       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.

RETURN VALUE         top

       No values are returned.

ERRORS         top

       The setkey() function shall fail if:

       ENOSYS The functionality is not supported on this implementation.

       The following sections are informative.

EXAMPLES         top



       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.

RATIONALE         top



       A future version of the standard may mark this interface as
       obsolete or remove it altogether.

SEE ALSO         top

       crypt(3p), encrypt(3p)

       The Base Definitions volume of POSIX.1‐2017, stdlib.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic
       form from IEEE Std 1003.1-2017, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The
       Open Group Base Specifications Issue 7, 2018 Edition, Copyright
       (C) 2018 by the Institute of Electrical and Electronics
       Engineers, Inc and The Open Group.  In the event of any
       discrepancy between this version and the original IEEE and The
       Open Group Standard, the original IEEE and The Open Group
       Standard is the referee document. The original Standard can be
       obtained online at .

       Any typographical or formatting errors that appear in this page
       are most likely to have been introduced during the conversion of
       the source files to man page format. To report such errors, see .

IEEE/The Open Group               2017                        SETKEY(3P)

Pages that refer to this page: stdlib.h(0p)crypt(3p)encrypt(3p)