Linux – find only files in directory with permissions not set to 644 on linux

command-line-interfacefindlinux

This is my first question although I've been lurking for a while.

Question:
I would like to use find to get only the files in a directory with permissions not set to 644 (or another permission value). Is there shorter way to write this or is the only way to just use the -perm and -or options and list each permission type except for 644?

This is part of a larger command that I was hoping to speed up:

find /path/to/dir/ -type f -print0 | xargs -0 chmod 644

I'm hoping that providing xargs only the file names that need updated will speed it up. The directory has ~ a million files but only ~10,000 usually need permissions updated. I think the command is slow because it is still piping all the files regardless. Maybe there is a more efficient approach to the larger command. Let me know if you know of one. I'd still like to know the answer to this question though. And btw, I can't update the permissions before adding the files to the directory.

Best Answer

The ! operator returns true when a condition is false.

So while -perm 0644 matches files that have rw-r--r-- permissions set, ! -perm 0644 matches those that don't have those permissions.

The command you need is:

find /path/to/dir/ -type f ! -perm 0644 -print0 | xargs -0 chmod 644

Related Solutions

How to master the UNIX find command

Well, as far as the -exec syntax goes, you could do like a lot of people, give up and use xargs:

find . -type f | xargs chown username

(or the files-with-spaces-and-other-nonsense-in-them-safe version)

find . -type f -print0 | xargs -0 chown username

Or, to try to remember the right thing to do with the semicolon, what you need to drill into your head is that you're using a semicolon to terminate the command that -exec is running, and you have to escape the semicolon because it has special meaning to bash. Which is why it's backslash semicolon. You seem to have the {} substitution part okay.

As to killing files and so on, if you're running something big and dangerous like you're talking about, first do this:

find . -type f -exec echo chown username {} \;

and review the results. This is basically a "dry run" where you're seeing the commands it would run if you let it. Definitely a good practice. Won't help with the .* problem, but you know not to do that one now. :)

Linux – How to set the file permissions permanently for a directory in Linux

It sounds from your description that the cron job just needs to read the files, which it should be able to do. Is the issue that you're trying to uncompress the files in place? Can you uncompress them to a temporary folder instead?

In order to modify the permissions of new files uploaded by FTP, you would need to change the umask of the FTP daemon process to 002. How to do that depends on the FTP server and Linux distribution.

Best Answer

Related Solutions

How to master the UNIX find command

Linux – How to set the file permissions permanently for a directory in Linux

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