The shell command line enables you to use strings of specially constructed character patterns for wildcard matches. This is a different simpler capability than that supported by GNU utilities such as
grep, which can use more complex patterns, known as expressions, to search through files or directories or to filter data input to or out of commands.
The shell’s pattern strings can be simple or complex, but even using a small subset of the available characters in simple wildcards can yield constructive results at the command line. Common characters used for shell pattern matching include the following:
*—Matches any character. For example, to find all files in the current directory ending in
.txt, you could use ...