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MV files fast: bulk rename several files at once on linux.

I’m still not super-familar with bash, but I love working in it — everything is faster. Take this handy dandy little line, which you can use to rename multiple files easily:

for f in *;do mv $f ${f/test/prod};done

I probably don’t need to tell those of you developing modules (where your primary files share the same prefix) how much of a time saver this is. For example, if you want to build your functionality using the imaginary example_mod module as a base, you could do this:

cp -rp example_mod my_mod
cd my_mod #otherwise you're gonna replace *BOTH* instances
for f in example_mod.*; do mv $f ${f/example_mod/my_mod};done

You still need to edit the info and module files so they don’t contain previously defined functions, but I suspect a little fancy sed work and you’d be all set. from Shell Geek EDIT: I’ve noticed a lot of people come here to try and figure out how bulk renaming works, so I feel like I should add some clarity. Let’s look at the command:

for f in *;do mv $f ${f/test/prod};done

Here’s what’s happening: for f in *; that’s a single command — if you didn’t notice — the semicolon indicates that the command ends after the asterix. We’re essentially saying “I’m starting a ‘for’ loop, wherein $f will stand for each file in my current directory”. The next command is

do mv $f ${f/test/prod};

The ‘do’ here is a part of the ‘for’ loop, it tells bash what we want to do for each file ($f) in the directory. In this case, we want to replace all instances of ‘test’ with ‘prod’. Let’s say I have 3 files. One is named ‘test.txt’, one is named ‘test.sh’, and one is named ‘thegreatest.as’. We are essentially running the following commands:

mv test.txt prod.txt
mv test.sh prod.sh
mv thegreatest.as thegreaprod.as

That is to say, the $f references our filename, whereas ${f/test/prod} says ‘replace any instances of “test” with “prod” in all of our filenames. This is where the syntax is a little weird, right? I don’t know enough about how {} function in bash to be entirely clear, but essentially, we say “take my variable $f. Replace whatever I say after this / with the next bit of text i have after the second /”. The format of var/find/replace should be very familiar to you if you use vim or anything that uses regexes, so I think both of us can just take the brackets as a magic eval for now. If you’ve got a nice story to tell about what brackets actually mean to bash, please let me know. Anyhow, after that line, we say

done

which closes the ‘for’ loop we opened with for f in *;. Hope this makes sense and helped you out. Leave a comment if it doesn’t or if I’ve left something out, and I’ll add more detail.