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Problem with using a sed to add escape character \ before $ and ' symbols

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# 1  
Old 03-02-2011
Problem with using a sed to add escape character \ before $ and ' symbols
Hi all,
I've got a problem with sed. Want to use it to add escape character \ before $ and ' symbols so

condition='1'$some will become condition=\'1\'\$some

Code:
echo "condition='1'$some" | sed 's/\($\)/\\\1/g'

is not working properly. Can somebody help me with this please?

Regards, Johny


Moderator's Comments:
Mod Comment Please use [code] and [/code] tags when posting code, data or logs etc. to preserve formatting and enhance readability, thanks.
Last edited by zaxxon; 03-02-2011 at 05:00 AM.. Reason: code tags
# 2  
Old 03-02-2011
Code:
$> cat infile
condition='1'$some
$> sed "s/['\$]/\\\&/g" infile
condition=\'1\'\$some

# 3  
Old 03-02-2011
Quote:
Originally Posted by zaxxon
Code:
$> cat infile
condition='1'$some
$> sed "s/['\$]/\\\&/g" infile
condition=\'1\'\$some

Thanks, much better but one problem: it cuts the end of string:

Code:
echo "cond='1'$some" | sed "s/['\$]/\\\&/g"

result
cond=\'1\'
# 4  
Old 03-02-2011
Quote:
Originally Posted by johny_be_good
Thanks, much better but one problem: it cuts the end of string:

Code:
echo "cond='1'$some" | sed "s/['\$]/\\\&/g"

result
cond=\'1\'
Its because the variable $some gets expanded. Escape the $ in the echo statement and try.
# 5  
Old 03-02-2011
I think that the problem comes from the echo statement.
The string to display is between ", the shell expands the variable $some which may be not defined.
# 6  
Old 03-02-2011
not actual
Last edited by johny_be_good; 03-04-2011 at 10:09 AM..
# 7  
Old 03-02-2011
What is the argument you pass to the script above..?
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