A little bit of sed/awk magic

Hi guys,

I'm looking for an expert who is familiar with sed and awk, I need to parse a text file using Bash. My text file looks something like this:

; this is a comment

[mapping]

; some more comments here
foo=bar
apple    =   banana

; and more comments
       qwerty=dvorak

[statement]
this is a block of text which should
be read verbatim, without any
; parsing of any kind = that was applied
to the = mapping section 

above.

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Basically what I need to do is:

1) In the "[mapping]" section of the file:
    a) Ignore lines that are pure whitespace or that start with a semicolon
    b) Get each mapping pair, e.g. "foo" and "bar", "apple" and "banana" etc
    c) Trim whitespace off the pairs

2) In the "[statement]" section of the file
    a) Get the entire block of text following the line that says [statement], verbatim, without any of the parsing or formatting that was done in the [mapping] section.

I hope this isn't too complicated. It doesn't need to be really robust, the example I gave above is about as bad as the text file will get and it can die horribly if it is malformed. I'm not concerned much with efficiency either (the file I'm parsing is always going to be pretty small), so whatever solution can read the file in over and over again, re-parse things more than it needs to etc.
LVL 31
Frosty555Asked:
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woolmilkporcConnect With a Mentor Commented:
1)

awk '/\[mapping\]/,/\[statement\]/ {if($0~"=") print $1 $2 $3}' inputfile

2) Where does the [statement] section end?
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wesly_chenCommented:
A2.
awk 'BEGIN{found=0;} /\[statement\]/ {found=1;} {if(found==1) print}'  /path-to-inputfile | tail -n+2
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wesly_chenCommented:
Here is another version of A2 by perl command line

perl -ne 'if (/\[statement\]/){$state=1; next;} print if ($state eq 1);'  /path-to-inputfile
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wesly_chenConnect With a Mentor Commented:
Small modification of awk in #36499522
awk 'BEGIN{found=0;} /\[statement\]/ {found=1;next} {if(found==1) print}'  /path-to-inputfile
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Frosty555Author Commented:
woolmilkporc:
awk '/\[mapping\]/,/\[statement\]/ {if($0~"=") print $1 $2 $3}' inputfile

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This successfully parses out the contents of the [mapping] section.

For your question, the [statement] block ends at the end of the file.

wesly_chen:
awk 'BEGIN{found=0;} /\[statement\]/ {found=1;next} {if(found==1) print}'  /path-to-inputfile

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This successfully grabs the [statement] block.

Thanks guys!
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