UNIX for Dummies Questions & Answers

Hello, I have a situation where I want to change a line of text in multiple files, but the problem is that I want to change the text to something unique for each file.

For example, let's say I have five files named bob.txt, joe.txt, john.txt, tom.txt, and zach.txt. Each of these files has a line (1st line) with the text "name = xxx". For each file, I want to replace the "xxx" with the name in each file name, such that bob.txt has the first line changed to "name = bob", the first line in joe.txt is changed to "name = joe", etc. I have some experience with sed and grep, but I'm not sure how I would use those in this situation. Thanks.

Code:

for i in bob.txt joe.txt john.txt tom.txt zach.txt
do
 sed '1s/name = xxx/name = '"${i%.*}"'/' $i > $$
 mv $$ $i
done

I tried this and got this message:

Missing $ on loop variable at chgnm.pl line 3

I made five files named like I said above and put name = xxx in each file, then I put what you typed into a perl script called "chgnm.pl", and that was the message I got.

That's not perl..it's a shell script...!!!

Oh... shit. I'm still a n00b, haha. I changed it to bash and it worked, thanks.

---------- Post updated at 03:51 PM ---------- Previous update was at 03:20 PM ----------

Ok, so how would I modify this is I wanted to change the text to "name = bob.txt" instead of just "name = bob"?

Just ${i} instead of ${i%.*} .

For information on what that means, see String Operations in the Advanced BASH Scripting Guide.