Quirk running Sed on Mac

Get Help Command Line
#1

Hi all, I ran into a problem during Lingua Franca. the sed command returned an error invalid command W. Searching for an answer brought me to this

If you are on a OS X, this probably has nothing to do with the sed command. On the OSX version of sed , the -i option expects an extension argument so your command is actually parsed as the extension argument and the file path is interpreted as the command code.

Try adding the -e argument explicitly and giving '' as argument to -i :

 sed -i '' -e "s/search string/replace string/" directory/file.extention ;

It links out https://stackoverflow.com/questions/7573368/in-place-edits-with-sed-on-os-x

Figured I'd bring it up in case anyone else uses OsX and ran into the same problem?
Lingua Franca - Error on Task 16 (sed)
#2

I had the same problem and could not make it work. It would be good if the run-through for the exercise was edited with the appropriate code for OSX.

#3

To clarify,

sed -i’.bak’ -e ‘s/lingua-franca/lingua_franca/g’ /.txt
did not work for me. It only worked after I removed the -e argument. I do not understand exactly why, but the following worked:

sed -i’-bak’ ‘s/Lingua-Franca/Lingua Franca/g’ /.txt

I think this may be due to running the bash shell rather than the zsh shell?

#4

It’s always useful to run man on anything that could be variable, man sed in this case would show how it would work w/ your system.

Rather than having lines that run in all systems it’d be useful if they make a passing note on accessing this help (…they might, I can’t say I’ve done this exercise).

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#5

Thanks, @toastedpitabread, that’s helpful! I agree that it would make sense to raise awareness in the instructions that each user needs to figure out how sed works on their system, maybe just a tip to try man sed.

#6

I believe it’s because OSX runs BSD sed whereas the instructions appear to be using GNU sed.


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