---
tags:
  - linux
---
https://linux.die.net/man/7/glob

**Wildcards**
- \*: any str, including empty
- ?: any single char

**Character classes** are wrapped with []. First char can't be ! and it can't be empty. Thus to match [ ] and ! we need to wrap them like so `[][!]`

**Ranges** two chars separated by `-`.

**Complementation** `[!..]` match any chars not in the character class.

**Pathnames** globbing applies to component seperately. `/` not allowed in character classes. Wildcards don't match `/`.
Dot files must be explicitly matched, thus `*` will not match it.

**Empty lists** A wildcard can expand into an empty list (e.g `*.gif` where no .gif exist). If the wildcard expands to an empty list or is invalid it will remain unchanged per POSIX specifications.
In bash `shopt -s nullglob` enables expanding into an empty list.

### Difference with Regular Expressions
With globbing we match filenames rather than text.