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I'm running the following command to add line numbers:

perl -pe '$_ = "$. $_"'

I can append the results to a file with:

cat test.txt | perl -pe '$_ = "$. $_"' >> test.txt

But if I try to replace the current contents the file ends up blank:

cat test.txt | perl -pe '$_ = "$. $_"' > test.txt

Why is this?

Philip Kirkbride
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    for in place editing, just use `perl -i -pe '$_ = "$. $_"' test.txt`... also there is a command `nl` for numbering purposes – Sundeep Jul 26 '17 at 14:09

0 Answers0