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Delete all lines starting with # character

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# 8  
Old 08-26-2017
I like this URL
The \s is in chapter "Perl Extensions".
In Linux the perl extensions sneak into the BRE and ERE, but they are not standard.
I would use them only in perl.
Code:
perl -ne '/^\s*#/ or print'

but not elsewhere
Code:
grep -v '^[[:space:]]*#'

Code:
sed '/^[[:space:]]*#/d'

Another one with awk
Code:
awk '$1!~/^#/'

These 2 Users Gave Thanks to MadeInGermany For This Post:
drl John K
# 9  
Old 08-26-2017
Quote:
Originally Posted by John K
...
Where can I read more about "\s" ? What is this operator called ? (So that I can google about it )
It's a "metacharacter" or a "shorthand character class" in a regular expression.
Any book, blog or webpage on regular expressions should mention it.

Here's the Wikipedia page on regular expressions; search for "\s" on that page:
Regular expression - Wikipedia

Here's Jan Goyvaert's website on regular expressions in general. Pretty decent stuff.
Regexp Tutorial - Shorthand Character Classes

In particular, if you are looking for using regular expressions in the Vim editor, then this page looks pretty good:

Vim Regular Expressions 101

The books mentioned at the bottom of the above page are good too.
Jeffrey Friedl's book on regular expressions is the most advanced and a gold mine of information.
These 2 Users Gave Thanks to durden_tyler For This Post:
drl John K
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