Wildcards

Wildcards may be used to specify a set of files on the command line:

	% ls *.txt
	jim.txt
	bob.txt
	%

In a shell environment wildcards are expanded on the command line, rather than within each command.  This means that expanded filenames are treated as text:

	% echo "These are my text files:" *.txt
	These are my text files: jim.txt bob.txt
	%

Wildcards may be matched within the current working directory or at the end of a pathname.  Matching in the middle of a pathname is not supported:

Good wildcard patterns:

	*.h
	:tmp:*.h
	"my disk:my folder:my *"

Bad wildcard patterns:

	*:tmp.h
	"my disk:*:my file"

Wildcard Summary

*	- Match zero or more characters.  For example, b* matches the files "b", "bat", "belfry", and so on.

?  -  Match exactly one character.  For example b? matches "bb", "bz, and so on.

[abc]  -  Match any character listed in the brackets.  For example b[cd] matches "bc" or "bd".

[a-d]  -  Match any character in the range "a" to "d".  For example, b[w-z] matches "bw", "bx", "by" or "bz".

[^abc]  -  Match any character not listed in the brackets.  For example b[!a-z] matches "b0" and "b2", but not "ba" or "bi".

\*  -  Match a literal "*".

\?  -  Match a literal "?".

\[  -  Match a literal "[".

Sample Patterns

*.txt  -  Match all files which end with ".txt".

b*  -  Match all files which start with "b".

*tt*  -  Match all files which contain a "tt" anywhere.

[abc]*  -  Match all files which start with an "a" or "b" or "c".

[a-zA-Z0-9]*  -  Match all files which start with an alphanumeric character.

b*[0-9]  -  Match all files which start with a "b" and end with a number.

Wildcards and Quotes

Macintosh filenames often contain spaces.  To allow matching on such names, the nShell allows quoting of wildcard specifications:

"my *"     Match all files which start with "my" and a space.

Note that the entire string is treated as a pattern. The command:

% echo "These are my files: my *"

would attempt to match files which start with "These are my...".  To list my files, I would use the command:

% echo "These are my files:" "my *"

In this case, only the second parameter is expanded as a wildcard.

Single quotes suppress wildcard expansion, as shown below.

Suppressing Wildcard Expansion

Strings contained within single quotes are not expanded:

	% echo 'my favorite pattern is *.txt'
	my favorite pattern is *.txt

Backslash characters may be used to force single characters to be treated literally.