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Allegro CL version 10.1
Unrevised from 10.0 to 10.1.
10.0 version


Arguments: context &key return

Finalize and return the SHA224 hash from context in a format determined by the return keyword argument.

return can be one of the following values:

cl-user(4): (setq c (sha224-init))
#S(excl::md-context :ctx 9183104 :size 28)
cl-user(5): (sha224-update c "foo")
cl-user(6): (sha224-final c :return :usb8)
#(8 8 246 78 96 213 137 121 252 182 ...)

;;  Potential problem with :return :integer (or :return unspecified
;;  as the default is :integer). The call is to SHA224-FILE which calls
;;  SHA224-FINAL and returns the value SHA224-FINAL returns.
;;  Here we get the sha224 value in a shell:
% openssl dgst -sha224 -hex uninstall.jpg 
SHA224(uninstall.jpg)= 012d03e402813fa87201182a9fa8dc71d5662e07a3298e6e3fee902a

;; Now we get it with SHA224-FILE:
cl-user(17): (sha224-file "~/uninstall.jpg")
cl-user(18): (format t "~x" *)

;; Note the hex values are the same but the leading 0 is not printed
;; by Lisp, which is dealing with the value as an integer. The leading
;; 0 is preserved when the :return is :hex:
cl-user(21): (sha224-file "~/unistall.jpg" :return :hex)

See MD*, SHA*, HMAC, and other message digest support in miscellaneous.htm. See also digest-final.

Copyright (c) 1998-2022, Franz Inc. Lafayette, CA., USA. All rights reserved.
This page was not revised from the 10.0 page.
Created 2019.8.20.

Allegro CL version 10.1
Unrevised from 10.0 to 10.1.
10.0 version