December 2018
Beginner
452 pages
12h 17m
English
Content preview from Learn Linux Shell Scripting - Fundamentals of Bash 4.4
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Character matching
We now know how we can search for whole words, even if we're not entirely sure about uppercase and lowercase yet.
We've also seen that regular expressions under (most) Linux applications are greedy, so we need to be sure that we're dealing with this properly by specifying whitespace and character anchors, which we will explain shortly.
In both these cases, we knew what we were looking for. But what if we do not really know what we are looking for, or perhaps only part of it? The answer to this dilemma is character matching.
In regular expressions, there are two characters we can use as substitutes for other characters:
- . (dot) matches any one character (except a newline)
- * (asterisk) matches any number of repeats of the ...
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