Bash – Loops using pipe and read

Perform some operation for every line in the output of a command, e.g. add .txt to every file in a directory:

ls /var/* | while read fname; do cp $fname $fname.txt; done

Instead of:

for fname in `ls /var/*`; do cp $fname $fname.txt; done

Neat trick I actually picked up in a job interview. Easier to read if the original command is long as it avoids the backticks, and bash is all about readability, right?? šŸ™‚

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