setkey - set encoding key

Syntax

#include <stdlib.h> void setkey(const char *key);

Description setkey() provides access to an encoding algorithm.

	key is a character array of length 64 bytes containing only bytes with numerical values of 0 and 1. This string is divided into groups of 8, where the low-order bit in each group is ignored. This gives a 56-bit key that is recorded. This is the key that will be used by the algorithm to encode the string block passed to the encrypt() function.
Notes	Since setkey() does not return a value, applications wishing to check for errors should set errno to 0, call setkey(), then test errno and, if it is non-zero, assume that an error has occurred.
See also	crypt(), encrypt(), stdlib.h.