This is not exactly a sed syntax problem, it's a find syntax problem.

The {} is a container that will replace the name of the file being processed by the sed command.

If you use find like this:

$ find . -type f -name *.py -exec head {} ;

This will find Python scripts and show you the head of each file. If you have three scripts in the current directory:

• 1.py


• 2.py


• 3.py

The {} will contain each file name and execute the head command on each file.

The -exec argument needs a ; at the end so it can recognize the end of the command arguments (sed in this case) but, in order to protect ; from expansion you need to escape it with the .

Remember that you can execute several commands at a time if you use the ;:

$ ls; pwd;

This will list directories (ls) and print your working directory (pwd). The -exec argument also needs the ;. But since you don't want to confuse the ; that separates commands with the ; that is part of the -exec argument of find, you need to escape it with the .

Alternatively, you can use quotes around the ;:

$ find /home/bruno/old-friends -type f -exec sed -i 's/ugly/beautiful/g' {} ";"

I hope I made myself clear