Linux 101 : Bash wildcards and metacharacters
In Linux, we could use wildcards when working with the names of the files.
Below are some of the wildcards:
• "*" : it matches any number of characters - zero or more -.
• "?" : This matches any single character.
• "[ ]" : it matches one or more of the characters that are in the brackets.
Metacharacters are as follows:
• ">" : redirection of output. The below example writes to the beginning of a file and overwrites its contents:
• ">>" : redirects output and appends it to the end of a file for example.
A complete example with "input" and "output" could be:
• "<<" : Input redirection. For example the below command takes input until we enter EOF.
• "|" : When using multiple commands, the output of one is the input of the other:
• ";" : sequence of command:
• "command &" : to run a command in the background, so we would have access to the command line prompt instead of waiting for the command to exit.
• "$(cmd)" : runs a command substitution. The below command displays "username is root" if we are logged in as root.
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