Linux and Unix Shell Programming

4.3. Using [ . . . ] and [ ! . . . ]

Use [...] to match any characters inside the brackets. This method also supports ranges by separating the range with a dash. To list all filenames that start with an ‘i’ or ‘o’:

						$ ls [io]* 
inetd.conf initrunlvl 
inputrc    issue 
info-dir   inittab 
ioctl.save issue.net
					

To match filenames that begin with ‘log.’, followed by a single number, followed by any other character. The [0–9] means any single number. The asterisk takes care of multiple numbers:

						$ ls log.[0-9]* 
log.0323  log.0324 
log.0325  log.0326
					

To list all filenames that have the same criteria as above but with no numbers, use the negation symbol (!) inside the bracket. [!0–9]* means it must not start with a digit.

						$ ls log.[!0-9]* 
log.sybase
					

To match ...