Linux: remove file extensions for multiple files

Question

I have many files with .txt extension. How to remove .txt extension for multiple files in linux?

I found that

rename .old .new *.old

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Answer 1

In Fish, you can do

for file in *.old
      touch (basename "$file" .old).new
end

Answer 2

The Perl version of rename can remove an extension as follows:

rename 's/\.txt$//' *.txt

This could be combined with find in order to also do sub-folders.

Answer 3

execute in bash linux

for i in *;do mv ${i} ${i/%.pdf/} ;done