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I am new to linux and im learning from a website, and this came up in the grep part of a course

i tried running the same code but without the $ symbol and it displays the same output, so im wondering what the role of the $ is

Shamirul Huda
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  • Are you aware of how that parameter to grep works? (same question as jons, but with a hint how to arrive there on your own...) – Yunnosch Jul 29 '23 at 06:42
  • To clarify, `grep` uses "regular expressions" (also known as "regex"), a way to specify patterns of text to mach against. – Ouroborus Jul 29 '23 at 06:43

1 Answers1

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In grep manual (run man grep in the terminal), you may find the following documentation regarding this:

Anchoring
   The caret ^ and the dollar sign $ are meta-characters that respectively match the empty string at the beginning and end of a line.

The intention in the use case you saw is clearly to ensure the filtered .txt filenames don't include extra characters at the end of the file extension. As you can see here, for example:

$ ls  
file1.txt  file2.txtz

$ ls | grep '.txt'
file1.txt
file2.txtz

$ ls | grep '.txt$'
file1.txt

Also, have a look at this.

Jardel Lucca
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