bionic (3) setkey.3posix.gz

Provided by: manpages-posix-dev_2013a-2_all bug

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.


NAME
       setkey — set encoding key (CRYPT)


SYNOPSIS
       #include <stdlib.h>

       void setkey(const char *key);


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.


RETURN VALUE
       No values are returned.


ERRORS
       The setkey() function shall fail if:

       ENOSYS The functionality is not supported on this implementation.

       The following sections are informative.


EXAMPLES
       None.


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.


RATIONALE
       None.


FUTURE DIRECTIONS
       None.


SEE ALSO
       crypt(), encrypt()

       The Base Definitions volume of POSIX.1‐2008, <stdlib.h>


       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition,
       Standard  for  Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electrical and Electronics Engineers,  Inc
       and  The  Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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
       http://www.unix.org/online.html .

       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
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .