/usr/share/acl2-8.0dfsg/books/hacking/progn-bang-enh.acl2 is in acl2-books-source 8.0dfsg-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | (in-package "ACL2")
; cert-flags: ? t :ttags ((defcode))
(certify-book "progn-bang-enh" ? t :ttags ((defcode)))
|