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setkey(3p) — Linux manual page

SETKEY(3P)              POSIX Programmer's ManualSETKEY(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

       Thesetkey() function provides access to an implementation-defined       encoding algorithm. The argument ofsetkey() 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 stringblock passed toencrypt().       Thesetkey() function shall not change the setting oferrno if       successful. An application wishing to check for error situations       should seterrno to 0 before callingsetkey().  Iferrno is non-       zero on return, an error has occurred.       Thesetkey() function need not be thread-safe.

RETURN VALUE        top

       No values are returned.

ERRORS        top

       Thesetkey() function shall fail if:ENOSYSThe functionality is not supported on this implementation.The following sections are informative.

EXAMPLES        top

       None.

APPLICATION USAGE        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 ofencrypt() does encoding but not decoding.

RATIONALE        top

       None.

FUTURE DIRECTIONS        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 athttp://www.opengroup.org/unix/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, seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html .IEEE/The Open Group                2017SETKEY(3P)

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

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