Learn Linux Shell Scripting - Fundamentals of Bash 4.4

Greediness

By default, regular expressions are considered greedy. This might seem a strange term to describe a technical concept, but it does fit really well. To illustrate why regular expressions are considered greedy, look at this example:

reader@ubuntu:~/scripts/chapter_10$ grep 'in' grep-file.txt We can use this regular file for testing grep.Did you ever realise that in the UK they say colour,but in the USA they use color (and realize)!reader@ubuntu:~/scripts/chapter_10$ grep 'the' grep-file.txt Did you ever realise that in the UK they say colour,but in the USA they use color (and realize)!

As you can see, grep does not by default look for full words. It looks at the characters in the file, and if a string matches the search (regardless ...