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

I've successfully used the following sed command to search/replace text in Linux:

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

However, when I try it on my Mac OS X, I get:

"command c expects \ followed by text"

I thought my Mac runs a normal BASH shell. What's up?

EDIT:

According to @High Performance, this is due to Mac sed being of a different (BSD) flavor, so my question would therefore be how do I replicate this command in BSD sed?

EDIT:

Here is an actual example that causes this:

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

Sinetris' answer is right, but I use this with find command to be more specific about what files I want to change. In general this should work (tested on osx /bin/bash):

find . -name "*.smth" -exec sed -i '' 's/text1/text2/g' {} \;

In general when using sed without find in complex projects is less efficient.

I've created a function to handle sed difference between MacOS (tested on MacOS 10.12) and other OS:

OS=`uname`
# $(replace_in_file pattern file)
function replace_in_file() {
    if [ "$OS" = 'Darwin' ]; then
        # for MacOS
        sed -i '' -e "$1" "$2"
    else
        # for Linux and Windows
        sed -i'' -e "$1" "$2"
    fi
}

Usage:

$(replace_in_file 's,MASTER_HOST.*,MASTER_HOST='"$MASTER_IP"',' "./mysql/.env")

Where:

, is a delimeter

's,MASTER_HOST.*,MASTER_HOST='"$MASTER_IP"',' is pattern

"./mysql/.env" is path to file

Your Mac does indeed run a BASH shell, but this is more a question of which implementation of sed you are dealing with. On a Mac sed comes from BSD and is subtly different from the sed you might find on a typical Linux box. I suggest you man sed.

sed -ie 's/old_link/new_link/g' *

Works on both BSD & Linux with gnu sed

Here is an option in bash scripts:

#!/bin/bash

GO_OS=${GO_OS:-"linux"}

function detect_os {
    # Detect the OS name
    case "$(uname -s)" in
      Darwin)
        host_os=darwin
        ;;
      Linux)
        host_os=linux
        ;;
      *)
        echo "Unsupported host OS. Must be Linux or Mac OS X." >&2
        exit 1
        ;;
    esac

   GO_OS="${host_os}"
}

detect_os

if [ "${GO_OS}" == "darwin" ]; then
    sed -i '' -e ...
else
    sed -i -e ...
fi

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.

Insead of calling sed with sed, I do ./bin/sed

And this is the wrapper script in my ~/project/bin/sed

#!/bin/bash

if [[ "$OSTYPE" == "darwin"* ]]; then
  exec "gsed" "$@"
else
  exec "sed" "$@"
fi

Don't forget to chmod 755 the wrapper script.

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)

As the other answers indicate, there is not a way to use sed portably across OS X and Linux without making backup files. So, I instead used this Ruby one-liner to do so:

ruby -pi -e "sub(/ $/, '')" ./config/locales/*.yml

In my case, I needed to call it from a rake task (i.e., inside a Ruby script), so I used this additional level of quoting:

sh %q{ruby -pi -e "sub(/ $/, '')" ./config/locales/*.yml}

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' *

Here's how to apply environment variables to template file (no backup need).

1. Create template with {{FOO}} for later replace.

echo "Hello {{FOO}}" > foo.conf.tmpl

2. Replace {{FOO}} with FOO variable and output to new foo.conf file

FOO="world" && sed -e "s/{{FOO}}/$FOO/g" foo.conf.tmpl > foo.conf

Working both macOS 10.12.4 and Ubuntu 14.04.5

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