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Bash Grundlagen
Basis Knowhow und Aufbau eines Skriptes
Skript Aufbau
Substring extraction in bash
To extract substrings from variables in bash, we can use the following syntax
${variable_name:offset:length}
Caveats:
If offset or length is negative, count from the end Negative values must be separated by a space away from the colon (:) to avoid being interpreted by bash as default value substitution. (See below for examples)
Get the file extension of a filename
$ filename=foobar.txt $ echo ${filename: -4} .txt
Get the file name without extension
$ filename=foobar.txt $ echo ${filename:0: -4} foobar