How to use SED to find and replace URL strings with the "/" character in the targeted strings? [duplicate]

Question

I'm attempting to use SED through OS X Terminal to perform a find and replace.

Imagine I have this string littered throughout the text file: http://www.find.com/page

And I want to replace it with this string: http://www.replace.com/page

I'm having trouble because I'm not sure how to properly escape or use the "/" character in my strings. For example if I simply wanted to find "cat" and replace with "dog" I've found the following command that works perfectly:

sed -i '' 's/cat/dog/g' file.txt

Does anyone have any ideas on how to achieve the same functionality only instead of cat and dog have strings or URLs that container the "/" character? I tried many different ways of escaping the "/" characters but then it seems as if SED can no longer "find" the string and it doesn't perform any find & replace actions.

Any help or tips are greatly appreciated.

Thanks!

Answer 1

/ is not the delimiter in sed commands, it's just one of the possible ones. For this example, you can for example use , instead since it does not conflict with your strings;

echo 'I think http://www.find.com/page is my favorite' | 
    sed 's,http://www.find.com/page,http://www.replace.com/page,g'

Answer 2

sed can take whatever follows the "s" as the separator. Since you are working with URL it is a good practice to use a different delimiter other than / to not confuse sed when your substitution ends and replacement begins.

However, having said that you can definitely use / if you wish too. You just need to escape the literal /.

So, you can either do:

sed 's/http:\/\/www.find.com\/page/http:\/\/www.replace.com\/page/g' input_file

or use a different delimiter to avoid making your cryptic sed more cryptic.

sed 's#http://www.find.com/page#http://www.replace.com/page#g' input_file