Using Glob Pattern with the find Utility

What is a glob pattern?

A glob pattern is a search query that contains wildcard characters. Bash allows three wildcard characters: *, ?, and []. The asterisk stands for any number of characters. A question mark means a single character of any kind.

Here is an example of glob patterns. The string README matches all following patterns:

• *ME
• READM?
• *M?
• R*M?

Square brackets indicate a set of characters at a specific position. For example, the pattern [cb]at.txt matches the cat.txt and bat.txt files. You can apply this pattern to the find call this way:

find . -name "[cb]at.txt"

Applying glob patterns

Let’s put glob patterns into practice. Let’s suppose that we do not know the location of the Bash README file. We should use the find utility in this case. Start searching with the find utility from the root directory. Now, we need a search condition. It’s a common practice to store documentation in directories called doc in Unix. Therefore, we can search files in these directories only. This way, we get the following find call:

find / -path */doc/*

The command shows us all documentation files on all mounted disks. This is a huge list. We can shorten it with an extra search condition. There should be a separate directory for the Bash documentation. The directory is called bash. Add this path as the second search condition. Then, we get the following command:

find / -path */doc/* -path */bash/*

The following find call provides the same result:

find / -path */doc/* -a -path */bash/*

Use the following terminal to run the commands discussed in this lesson.