# Sed -e 'Unterminated 's' command

Im trying to escape all the backslashes from some text generated by figlet. Here is what I have so far.

``````figlet -f \$font -t "Foo Bar" | sed -e "s|\\|\\\\|g"
``````

This doesn't work for some reason, but this does.

``````figlet -f \$font -t "Foo Bar" | sed -e "s| |X|g"
``````

The double quotes do not protect the backslashes that are inside the `sed -e "s|\\|\\\\|g"` from the shell's attempts to parse them. If you use a simpler example you can see this a bit more easily:

``````\$ echo 'blah\blah'| sed -e "s|\\|blah|g"
sed: -e expression #1, char 10: unterminated `s' command

\$ echo 'blah\blah'| sed -e 's|\\|blah|g'
blahblahblah
``````

If you want to use the first form of your `sed` you need to switch it to single quotes instead of double.

``````\$ figlet -t "Foo Bar" | sed -e 's|\\|\\\\|g'
_____             ____
|  ___|__   ___   | __ )  __ _ _ __
| |_ / _ \\ / _ \\  |  _ \\ / _` | '__|
|  _| (_) | (_) | | |_) | (_| | |
|_|  \\___/ \\___/  |____/ \\__,_|_|
``````

If you have to use double quotes, then you need more backslashes to escape the shell and `sed`:

``````\$ figlet -t "Foo Bar" | sed -e "s|\\\|\\\\\\\|g"
_____             ____
|  ___|__   ___   | __ )  __ _ _ __
| |_ / _ \\ / _ \\  |  _ \\ / _` | '__|
|  _| (_) | (_) | | |_) | (_| | |
|_|  \\___/ \\___/  |____/ \\__,_|_|
``````
• Oh wow thats interesting. So everything works fine now that I'm in single quotes. But what if I want to also add environment variables in there? I can't do that with single quotes (I don't need it for what I'm working on, but I'm curious of how to get around this) – Amlesh Sivanantham Aug 24 '18 at 0:10
• @AmleshSivanantham - you have to escape the backslashes with more if you want to use double quotes. – slm Aug 24 '18 at 0:43