Regular Expression not working with sed Post: 302570116

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Top Forums Shell Programming and Scripting Regular Expression not working with sed Post 302570116 by bghosh on Wednesday 2nd of November 2011 12:17:38 PM

11-02-2011

Registered User

Regular Expression not working with sed

Hi All,

I am facing some problems with regular expression with sed.

I have a .txt file with the contents as below:

This is a dummy file

# File created to test execution of regular expression.

Hope it works out.

As in the above contents there is a blank line which does not contain anything other than a new line (Enter Key of keyboard).

I execute the command

sed '/^$/d' regexp.txt

And it prints the complete text along with the blank lines. I cannot figure it out. Is there anything wrong in the syntax?

Next thing I tried is with the text

This is a dummy file
# File created to test execution of regular expression.
Hope it works out.

I tried the following command

sed '/^#/d' regexp.txt

And it prints the complete text with the line which has # in the begining.

My requirement is that if on every line the first character is any special character such as _,-,,(comma),',",$,^,#,~ etc, it should delete the line along with all the empty lines should be deleted.

help is highly appreciated.

bghosh

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