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Can someone please explain sed -n '/^$/!{s/<[^>]*>//g;p;}' filename

 
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Top Forums UNIX for Dummies Questions & Answers Can someone please explain sed -n '/^$/!{s/<[^>]*>//g;p;}' filename
# 1  
Old 03-26-2012
Can someone please explain sed -n '/^$/!{s/<[^>]*>//g;p;}' filename
I came across this sed expression, and it does exactly what I want.
However I haven't got the faintest clue how it does it and thus do not feel capable of using it.

Can someone please explain how this expression works?
(I used it to remove html tags in a html file I was converting to text)

sed -n '/^$/!{s/<[^>]*>//g;p;}' filename


The more detail the more I love you :-)
Thanks heaps,
# 2  
Old 03-26-2012
Hi maximus73,

Code:
sed -n '        ## Disable printing by default.
/^$/!{            ## In lines with content...
s/<[^>]*>//g;    ## Remove all conten between '< ... >'. Apply it many times for each line.
p;                ## Print line.
}' filename        ## File to process.

This User Gave Thanks to birei For This Post:
maximus73
# 3  
Old 03-26-2012
The way I see it is, this would remove all the tags from an xml file. But how this is achieved is, in all blank lines /^$/, don't do this s/<[^>]*>//g;p;

!{s/<[^>]*>//g;p;} --> Not of {substitute contents in <> including <> with null}

Which looks like an equivalent of sed 's/<[^>]*>//g' filename

It appears to be an overkill. I could be wrong. May be someone more experienced in sed would know why it is the way it is.
This User Gave Thanks to balajesuri For This Post:
maximus73
# 4  
Old 03-26-2012
Could you tell us which part of the code you don't understand ?

If you understand nothing, reading the following would be a good start :

http://pubs.opengroup.org/onlinepubs...html#tag_09_03

[Appendix A] A.2 Syntax of sed Commands

[Chapter 3] 3.2 A Line-Up of Characters

Then tell us which part of the code you don't understand
This User Gave Thanks to ctsgnb For This Post:
nirjhar17
 
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