using the find command to find all files you have read access to

[fishjie]

Hi, I'm going through the exercises in Practical Guide to Linux Commands, Editors, and Shell Programming. One of them consists of using the find command to find all files you have read access to. At first I thought I could use something like -perm /o=r. But I also need to return stuff where the owner has read permission, and I am the owner of the file, or stuff where the group has read permission, and I am in the group. How do I do that? Thanks.

[AsusDave]

What about the -readable option?
From the man page

-readable
Matches files which are readable. This takes into account
access control lists and other permissions artefacts which the
-perm test ignores. This test makes use of the access(2) system
call, and so can be fooled by NFS servers which do UID mapping
(or root-squashing), since many systems implement access(2) in
the client’s kernel and so cannot make use of the UID mapping
information held on the server.

[fishjie]

That would work, except that when I look at my find man page, i don't see that option. I'm running Fedora core. Is there another version of find?

[drl]

Hi.

This seems to work in Fedora 12:

#!/usr/bin/env bash

# @(#) s1	Demonstrate "-readable" find option, Fedora 12.

echo
set +o nounset
LC_ALL=C ; LANG=C ; export LC_ALL LANG
echo "Environment: LC_ALL = $LC_ALL, LANG = $LANG"
echo "(Versions displayed with local utility \"version\")"
version >/dev/null 2>&1 && version "=o" $(_eat $0 $1) find
set -o nounset

echo
echo " Results:"
find .. -readable -type d

exit 0

producing:

% ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 2.6.31.6-166.fc12.i686.PAE, i686
Distribution        : Fedora release 12 (Constantine)
GNU bash 4.0.35
find (GNU findutils) 4.4.2

 Results:
..
../find-readable
../collect-for-new-box

Best wishes ... cheers, drl