/usr/share/acl2-6.3/books/oslib/ is in acl2-books 6.3-5.
This file is owned by root:root, with mode 0o755.
..
/usr/share/acl2-6.3/books/oslib/argv-raw.o
/usr/share/acl2-6.3/books/oslib/argv.o
/usr/share/acl2-6.3/books/oslib/catpath.o
/usr/share/acl2-6.3/books/oslib/date-raw.o
/usr/share/acl2-6.3/books/oslib/date.o
/usr/share/acl2-6.3/books/oslib/getpid-raw.o
/usr/share/acl2-6.3/books/oslib/getpid.o
/usr/share/acl2-6.3/books/oslib/logic-defs.o
/usr/share/acl2-6.3/books/oslib/ls-raw.o
/usr/share/acl2-6.3/books/oslib/ls.o
/usr/share/acl2-6.3/books/oslib/mkdir-raw.o
/usr/share/acl2-6.3/books/oslib/mkdir.o
/usr/share/acl2-6.3/books/oslib/portcullis.o
/usr/share/acl2-6.3/books/oslib/read-acl2-oracle.o
/usr/share/acl2-6.3/books/oslib/rmtree-raw.o
/usr/share/acl2-6.3/books/oslib/rmtree.o
/usr/share/acl2-6.3/books/oslib/tempfile.o