setkey(3C)

NAME

     setkey - set encoding key

SYNOPSIS

     #include <stdlib.h>

     void setkey(const char *key);

DESCRIPTION

     The setkey() function provides (rather primitive) access  to
     the  hashing  algorithm  employed by the crypt(3C) function.
     The argument of setkey() is an array of length 64 bytes con-
     taining  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  will  be  used
     with  the  algorithm  to  encode  a  string  block passed to
     encrypt(3C).

RETURN VALUES

     No values are returned.

ERRORS

     The setkey() function will fail if:

     ENOSYS
           The functionality is not supported on this implementa-
           tion.

USAGE

     In some environments, decoding may not be implemented.  This
     is related to U.S. Government restrictions on encryption and
     decryption routines: the DES decryption algorithm cannot  be
     exported  outside the U.S.A. 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  decod-
     ing.

     Because setkey() does not return a value, applications wish-
     ing  to  check  for  errors should set errno to 0, call set-
     key(), then test errno and, if it  is  non-zero,  assume  an
     error has occurred.

ATTRIBUTES

     See attributes(5) for descriptions of the  following  attri-
     butes:

     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | MT-Level                    | Safe                        |
    |_____________________________|_____________________________|

SEE ALSO

     crypt(3C), encrypt(3C), attributes(5)