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Regular Expression not working with sed

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# 1  
Old 11-02-2011
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.
# 2  
Old 11-02-2011
Did you create the .txt file in Windows? It will contain garbage carriage returns which sed will consider as part of the text.
# 3  
Old 11-02-2011
yes I did.

So what would you suggest?
# 4  
Old 11-02-2011
Use dos2ux or dos2unix command...
# 5  
Old 11-02-2011
isn't this thread the same as this thread?
Please don't double-post - stick to one thread.
And also, please, use code tags when posting data/code samples.
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