Quick question on expanding variable


 
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# 1  
Old 08-08-2013
Quick question on expanding variable

Code:
s=`awk '{ print $0}' /Applications/Relink.app/z_cloudline.txt`
sed -n '"$s"' /var/mobile/Library/iFile/Bookmarks.plist > /var/mobile/originalip.txt

What is the problem with that code ?
With variable it only outputs:
Code:
sed: -e expression #1, char 1: unknown command: `"'

If I use the normal version that doesn't use a variable:
Code:
sed -n '746p' /var/mobile/Library/iFile/Bookmarks.plist > /var/mobile/originalip.txt

it works flawlessly.



Thanks in advance
# 2  
Old 08-08-2013
Because variable expansion doesn't happen inside single quotes or strong quotes.
Code:
sed -n '"$s"'

Remove single quotes and use just double quotes or weak quotes instead.
# 3  
Old 08-08-2013
Since this article here didn't help me either on the subject of weak and strong quotes.
http://zurlinux.com/?tag=weak-quote

OK, using only doulbe quotes helps...

what are weak quotes again ?
# 4  
Old 08-08-2013
This might help:

Strong versus Weak quoting
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