This may not be a bug, this may be intentional - however it was considered pretty damn weird when encountered and worth a mention. Say we have user 'bob', he is the owner of file 'accounting.txt' and 'accounting.txt' has group 'staff' attributed to the file which 'bob' is a part of. If the permissions for the file only have group perms (e.g 0060), 'bob' will not be able to access 'accounting.txt', however all other users in the 'staff' group will have access. Replication via CLI: touch myfile.txt && chown `whoami`:`groups | awk '{print $2}'` myfile.txt && chmod 0040 myfile.txt && cat myfile.txt System: Debian 6.0.1 Arch: x86_64 Kernel: 2.6.39
Yes, this works as defined in the standard. If user is the owner, we check against owner bits. If the user is not the owner, but belongs to the owner group, we check against group bits. If user falls into neither of previous cathegories, we use 'other' bits.