Wildcards in Linux

Wildcards are a set of building blocks that allow you to create a pattern defining a set of files or directories.

Here is the basic set of wildcards:

• * - represents zero or more characters


• ? - represents a single character


• [] - represents a range of characters

 

 Wildcards may be used with any command.

 

* in Linux

It represents zero or more characters. If you want to list all the files and directories then this wildcard is very beneficial.In simple words, whenever you use * means it will include all the character.

ls * 

E.g.  if you want to list all the directory which starts with D. Then you just have to write.

ls D*

it will list all the directories and files of those directories which starts with D.

 

suppose you want to search all files with extension png.

ls path *.png

Here path is from where you want to list all png.

 

? in Linux

it represents one character. This wildcard is used as a filter like if you want to search a directory whose second letter is o or whose extension is of 3 words.. etc. It is mainly used with * wildcard.

it means list all the file whose first letter is an unknown but second character is o and i do not care about remaining characters in the file name.

it means I do not care about the file name. I care about extension only whose length consists of 3 characters.

[] in Linux

It represents the range of characters. so, it is also called range operator.

suppose you want to see all files or folders whose name starts with M, V and f.

or you want to list all files which is in range between A-F.

 

i guess you got the basic understanding about wildcard.