Any way to force files to inherit owner permissions from parent directory?

Question

Is there any way to force a file, created within a directory, to inherit ownership from the parent directory? I tried the sticky bit, but that doesn't seem to work.

Example of what I'm looking for:

drwxrwxr-x www-data somegroup parentdir

When parentdir/newfile.htm is created by someuser:

-rwxrwxr-x www-data somegroup newfile.htm

NOT

-rwxr-xr-x someuser somegroup newfile.htm

Any way this can be done? Thank you!

Solution

Linux has something known as Access Control List (ACL). This is a way to extend standard unix permissions and fine tune them. One of the advantages is that it does have inheritance. What could be done, has been referenced by a related post on serverfault, and in your particular case:

sudo setfacl -Rdm g:somegroup:rwx /path/to/parent

As for forcing the files to be owned by the same user, it has been discussed in Getting new files to inherit group permissions on Linux, however forcing the same owner on each file is far more troublesome than having the file to be forced to have same group ownership as done via setfacl. If the group has exactly the same permissions as the owner, there's no point to force the same ownership. Of course, you could always use inotifywait and trigger chown upon file creation, but that's pointless since group ownership already gives you control over the file.

See also:

• Getting new files to inherit group permissions on Linux

Comments

[muru]

The sticky bit or the setgid bit?

[S. Wyatt Young]

@muru, I believe they're one in the same. What I'm calling the sticky bit is the flag that makes sure children inherit the group owner from the parent directory.

[muru]

That's the setgid bit. The sticky bit is what you see on /tmp - which prevents others from deleting your files.

[S. Wyatt Young]

@muru: Ah! Thank you for clarifying that bit for me.

[Lucas Pottersky]

i'm always surprised how technologies can do crazy things, but not simple things like that. (at least not in a straight-forward way)

[S. Wyatt Young]

Not what I'm looking for. I'm looking to avoid changing permissions manually. Also, while HTML files don't need executability, scripts do. I might just be running scripts. :)

[WinEunuuchs2Unix]

OP has abandoned Ask Ubuntu and no answers with upvotes on this question. So +1 not just for a good answer but also to prevent the software from bumping this to the home page for infinity :)

[Sergiy Kolodyazhnyy]

@WinEunuuchs2Unix Yeah, it's an abandoned question, but it might be useful to some :) Thanks, btw

[WinEunuuchs2Unix]

I guess what I meant to say is OP won't accept answer nor upvote it. Happy New Year in CO in one hour 51 minutesBTW :)

[Sergiy Kolodyazhnyy]

@WinEunuuchs2Unix Happy New Year to you,too ! It's actually going to be in 1 hour and 51 minutes or so - it's 10:14 pm here. Eh, OP doesn't need to accept - if others find it useful, it's enough for me :)