Mastering `du –exclude` in Linux: Exclude Directories for Accurate Disk Usage

Well, let me tell ya, if you ever been workin’ with a Linux system and needed to check how much space a directory is takin’ up, you might’ve used the ‘du’ command. That little command can show ya the disk usage, but sometimes, you don’t wanna include certain files or directories in that calculation. Now, there’s this fancy thing called the ‘–exclude’ option. It lets ya leave out specific files or directories from the result. Don’t worry, I’ll explain how it all works, so you don’t get all tangled up in tech talk.

What is the ‘du’ command?

The ‘du’ command stands for ‘disk usage.’ It’s a way to see how much space a directory or file is takin’ up. When you run the ‘du’ command, it gives ya a summary of how much space each file or folder is usin’. It can be real handy when you wanna clean up your system and see which folders are takin’ up too much space.

Excluding directories with the ‘du’ command

Now, let’s say you’ve got a big ol’ directory full of files, and you only care about the size of the rest, not one or two specific directories inside it. That’s where the ‘–exclude’ option comes in handy. This option lets you tell ‘du’ to ignore certain files or folders while it does its thing.

For example, if you wanted to check the disk usage of everything except the /home directory, you could run a command like this:

du --exclude=/home /

Now, what this does is it tells ‘du’ to ignore the /home directory and any files or folders inside it. If you want to exclude everything inside a specific folder, you can use the wildcard ” to make sure ‘du’ skips everything inside that folder, like this:

du --exclude=/home/ /

Why use ‘–exclude’?

Well, there might be a few reasons ya’d wanna use this option. First off, maybe you got a folder that’s real big and full of files you don’t care about, like backups or log files. Using ‘–exclude’ keeps ‘du’ from counting those files, so you get a clearer picture of the rest of your system’s disk usage. It also makes your command run faster because it ain’t got to count every little thing in the excluded directories.

How to use ‘–exclude’ with specific patterns

Sometimes, you might not want to exclude a whole directory but just certain types of files. For instance, if you don’t want any ‘.log’ files in the report, you can use a pattern to match those files. Like this:

du --exclude=.log /

This will tell ‘du’ to ignore any file that ends in ‘.log’. You can also use other patterns, like ‘.jpg’ to exclude all the JPEG image files. It’s pretty flexible that way.

Using ‘–exclude-from’ for multiple files

Now, if you got a bunch of different files or directories you wanna exclude, you don’t have to write out each one on the command line. Instead, you can use the ‘–exclude-from’ option, and point to a file that contains a list of all the files and directories you wanna leave out. That way, ‘du’ will check that list and exclude everything that’s mentioned in it. Here’s an example:

du --exclude-from=/path/to/exclude_list /

Each line in that exclude list file should have the full path to the files or directories you want to exclude. It’s a good way to keep things organized if you have a lot to exclude.

Keep in mind some things

Now, I should mention, when you use ‘–exclude’, you’re still gonna see the size of the excluded files and directories listed in the output. It just won’t be counted toward the overall disk usage. You’ll still know that they’re there, but you don’t have to worry about them messin’ up your calculations.

Also, this works on files and directories, but be careful with the patterns you use. Sometimes, a pattern might match more than you expect, and you’ll end up excluding more than you wanted. It’s always good to double-check what you’re excluding, just to make sure ya didn’t miss anything important.

Other ways to exclude directories from search commands

If you’re also using the ‘find’ command and want to exclude directories from search results, there’s a couple of other tricks you can use. You can use the ‘-path’ option to specify which directories to skip, and then the ‘-prune’ option to stop the ‘find’ command from goin’ into those directories. Here’s an example:

find / -path /home -prune -o -print

In this case, ‘find’ will skip over the ‘/home’ directory and keep lookin’ in the rest of the system. It’s another way to avoid dealing with directories you don’t need to bother with.

Conclusion

Well, there you go. If you need to exclude certain files or directories from the ‘du’ command, the ‘–exclude’ option is the way to go. It’s simple to use, and it can save ya time and effort when you’re tryin’ to check disk usage without bein’ bothered by certain files. Whether you’re a seasoned pro or just learnin’ the ropes, this is a good trick to keep in your back pocket.

Tags：[du command, Linux du exclude, disk usage, Linux command, exclude directories, exclude files, Linux tutorial, du exclude example]