Permissions are the unix way of controlling access to resources such as files, directories and devices and may be specified for an owner, group, or all users.

learn more… | top users | synonyms (1)

56
votes
5answers
5k views

Redirecting stdout to a file you don't have write permission on

When you attempt to modify a file without having write permissions on it, you get an error: > touch /tmp/foo && sudo chown root /tmp/foo > echo test > /tmp/foo zsh: permission ...
15
votes
3answers
3k views

I accidentally chmod -R +x on a directory. How do I restore the correct permissions?

Well, to be specific, it was chmod -R 755. Now every file is executable, which I don't want. I am thinking that I should look at the first two bytes of each file for the #!, but will this cover ...
103
votes
1answer
125k views

How to set default file permissions for all folders/files in a directory?

I want to set a folder such that anything created within it (directories, files) inherit default permissions and group. Lets call the group "media". And also, the folders/files created within the ...
5
votes
2answers
342 views

What files in /var need to have specific owners?

I accidentally wreaked unknown amounts of havoc on my web server by running sudo chown -R myuser:mygroup * .* in /var/www, not remembering that .* would include the parent directory (as ..). I ...
9
votes
3answers
5k views

How to make a folder private?

I'm using Ubuntu with several users and I want to make folders viewable just for a specific user. Any idea how to do it?
8
votes
4answers
4k views

Downsides of umask 077?

What are the cons, for having a restrictive umask of 077? A lot of distros (I believe all, except Red Hat? ) have a default umask of 022, configured in /etc/profile. This seems way too insecure for a ...
2
votes
2answers
2k views

How to set up file permissions/ownership for FTP/Apache/PHP on CentOS

I have basic understanding of chmod and CentOS file permissions. 777 stands for 111111111 and rwx for each root, group, user, etc. What I can't get my head around is setting up Apache, FTP and PHP to ...
15
votes
7answers
11k views

What to use to backup files, preserving ACLs?

When using the tar utility to store files in backups one loses the extended ACLs. Is there some commonly used and not hackish solution (like: create a script that will recrate the ACLs from scratch) ...
6
votes
5answers
268 views

Changing Unix group for files

I have a file that a colleague and I are editing together, on a Unix system. We are using Unix group permissions to edit it. We have one Unix group that we are both members of. Whenever I save the ...