Why is $(...) preferred over `` (backticks)?
For several reasons:
- It makes nesting command substitutions easier. Compare:
x=$(grep $(dirname "$path") file) x=`grep \`dirname "$path"\` file`
- It's easier to read.
Newbies who see $() don't normally press the wrong keys. On the other hand, newbie who see `cmd` often mangle it into 'cmd' because they don't know what a backtick is.
Backslashes (\) inside backticks are handled in a non-obvious manner. (Example desired!) Inside $(), there are no such surprises.
The only time backticks are preferred is when writing code for the oldest Bourne shells, which do not know about $().