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question about variables with sed

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# 1  
Old 06-09-2009
question about variables with sed
Hi,
I am trying to do some mass replacements in lots of scripts, and using sed.
However sed doesn't seem to like to be able to dereference variables within the substitute clause. For example:

tab=newtable
cat f1 | sed 's/oldtable/$tab/g' doesn't work.
it would replace oldtable with the literal ( $tab ).

I've tried quoting out the $, using eval etc.. but nothing seems to work.

Any ideas are appreciated.

Thanks,
floyd
# 2  
Old 06-09-2009
Single quotes prevent the shell to expand variables, use double quotes instead. The use of cat with sed is redundant, this should sufficient:

Code:
sed "s/oldtable/$tab/g" f1

Regards
# 3  
Old 06-09-2009
Quote:
Originally Posted by Franklin52
Single quotes prevent the shell to expand variables, use double quotes instead. The use of cat with sed is redundant, this should sufficient:

Code:
sed "s/oldtable/$tab/g" f1

Regards
Darn, I can't believe I missed that !!

Thanks Franklin, much obliged to you.

Floyd
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