4.3.8 Shell wildcards

Often you want a command to work with a group of files without typing all of them. The filename expansion pattern using the shell wildcards facilitate this needs.

• *

  • This matches any group of 0 or more characters.

  • This does not match a filename started with ".".

• ?

  • This matches exactly one character.

• [...]

  • This matches exactly one character with any character enclosed in brackets

• [a-z]

  • This matches exactly one character with any character between a and z.

• [^...]

  • This matches exactly one character other than any character enclosed in brackets (excluding "^").

For example, try the following and think yourself:

     $ mkdir junk; cd junk; touch 1.txt 2.txt 3.c 4.h .5.txt
     $ echo *.txt
     1.txt 2.txt
     $ echo *
     1.txt 2.txt 3.c 4.h
     $ echo *.[hc]
     3.c 4.h
     $ echo .*
     . .. .5.txt
     $ echo .[^.]*
     .5.txt
     $ echo [^1-3]*
     4.h
     $ cd ..; rm -rf junk