Re: [OT] sed expression wildcard bafflement

[David Jardine <david@jardine.de>]

On Fri, Oct 17, 2003 at 03:56:39PM -0400, Nori Heikkinen wrote:
> a friend just asked me about a shell script she's trying to write.
> she's got a file that looks like this:
> 
>   blah blah thi. blah thi. blah blah
>   blah thi. blah thi. blah blah blah
> 
> &c. -- lots of "thi."s in there.
> 
> she's trying something equivalent to:
> 
>   word1=thi.;
>   word2=this;
>   sed 's/$word1/$word2/g' file > file.new;

Try using double quotes, ie:

	sed "s/$word1/$word2/g" file > file.new;


and thank Colin Watson for answering this sort of question 
so many times ;-)

> 
> and it doesn't replace.
> 
> i can replicate this from the command line.  the only way i can make
> it work is to type out
> 
>   sed 's/thi./this/g' file > file.new;
> 
> escaping the period in $word1 does nothing.
> 
> are we just misunderstarding the sed command somehow?  otherwise,
> afa[we]k, this is totally weird ...
> 
> thanks,
> 
> </nori>
> 
> -- 
>     .~.      nori @ sccs.swarthmore.edu
>     /V\  http://www.sccs.swarthmore.edu/~nori/jnl/
>    // \\          @ maenad.net
>   /(   )\       www.maenad.net
>    ^`~'^
>             get my (*new*) key here:
>    http://www.maenad.net/geek/gpg/7ede5499.asc
>       (please *remove* old key 11e031f1!)