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Top Forums Shell Programming and Scripting Delete all lines starting with # character Post 303002532 by durden_tyler on Saturday 26th of August 2017 05:40:27 PM
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:
 

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HXEXTRACT(1)							  HTML-XML-utils						      HXEXTRACT(1)

NAME
hxextract - extract selected elements from a HTML or XML file SYNOPSIS
hxextract [ -h | -? ] [ -x ] [ -s text ] [ -e text ] [ -b base ] element-or-class [ -c configfile | file-or-URL ] DESCRIPTION
hxextract outputs all elements with a certain name and/or class. Input must be well-formed, since no HTML heuristics are applied. OPTIONS
The following options are supported: -x Use XML format conventions. -s text Insert text at the start of the output. -e text Insert text at the end of the output. -b base URL base -c configfile Read @chapter lines from configfile (lines must be of the form "@chapter filename") and extract elements from each of those files. -h, -? Print command usage. OPERANDS
The following operands are supported: element-or-class The name of an element to extract (e.g., "H2"), or the name of a class preceded by "." (e.g., ".example") or a combination of both (e.g., "H2.example"). file-or-URL A file name or a URL. To read from standard input, use "-". ENVIRONMENT
To use a proxy to retrieve remote files, set the environment variables http_proxy and ftp_proxy. E.g., http_proxy="http://localhost:8080/" BUGS
Remote files (specified with a URL) are currently only supported for HTTP. Password-protected files or files that depend on HTTP "cookies" are not handled. (You can use tools such as curl(1) or wget(1) to retrieve such files.) SEE ALSO
hxselect(1) 6.x 10 Jul 2011 HXEXTRACT(1)
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