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Passing SED variable

Passing SED variable

Passing SED variable

This is one of those things that always seems to bite me.

I have the following in my script -
sed -i '284s/"[^"]*"/"mclane.com mclane.mclaneco.com"/g' <filename>

I need to configure the command so the 284 line number can be read as $ln in case the file
gets modified and the line number that actually needs to be edited changes.

I thought the following would work but that is not the case.

sed -i "$ln s/"[^"]*"/"mclane.com mclane.mclaneco.com"/g" <filename>

Thank you for your insight and assistance.


I.T. where a world of choas and confusion comes down to nothing but 1s and 0s.

RE: Passing SED variable


That would be correct for Sed, however the shell will probably yell at you because of unterminated string :
sed -i "$ln s/"[^"]*"/"mclane.com mclane.mclaneco.com"/g" <filename>       

You can either :

CODE --> line

# escape internal double quotes
sed -i "$ln s/\"[^\"]*\"/\"mclane.com mclane.mclaneco.com\"/g" <filename>

# double quote ( or not quote ) only the variable
sed -i "$ln"' s/"[^"]*"/"mclane.com mclane.mclaneco.com"/g' <filename>
sed -i $ln' s/"[^"]*"/"mclane.com mclane.mclaneco.com"/g' <filename> 


RE: Passing SED variable


Thank you. The single, double quoting, triple single quotes is always fun to attempt to keep straight.

I went with double quoting the variable and then using the single quotes which are more sed "standard" for syntax.

Thank you once again.


I.T. where a world of choas and confusion comes down to nothing but 1s and 0s.

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