sed command with -i option failing on Mac, but works on Linux

If you use the -i option you need to provide an extension for your backups.

If you have:

File1.txt
File2.cfg

The command (note the lack of space between -i and '' and the -e to make it work on new versions of Mac and on GNU):

sed -i'.original' -e 's/old_link/new_link/g' *

Create 2 backup files like:

File1.txt.original
File2.cfg.original

There is no portable way to avoid making backup files because it is impossible to find a mix of sed commands that works on all cases:

  • sed -i -e ... - does not work on OS X as it creates -e backups
  • sed -i'' -e ... - does not work on OS X 10.6 but works on 10.9+
  • sed -i '' -e ... - not working on GNU

Note Given that there isn't a sed command working on all platforms, you can try to use another command to achieve the same result.

E.g., perl -i -pe's/old_link/new_link/g' *


I believe on OS X when you use -i an extension for the backup files is required. Try:

sed -i .bak 's/hello/gbye/g' *

Using GNU sed the extension is optional.


This works with both GNU and BSD versions of sed:

sed -i'' -e 's/old_link/new_link/g' *

or with backup:

sed -i'.bak' -e 's/old_link/new_link/g' *

Note missing space after -i option! (Necessary for GNU sed)


Had the same problem in Mac and solved it with brew:

brew install gnu-sed

and use as

gsed SED_COMMAND

you can set as well set sed as alias to gsed (if you want):

alias sed=gsed

Or, you can install the GNU version of sed in your Mac, called gsed, and use it using the standard Linux syntax.

For that, install gsed using ports (if you don't have it, get it at http://www.macports.org/) by running sudo port install gsed. Then, you can run sed -i 's/old_link/new_link/g' *