How can I convert a string containing glob characters such as
/var/lib/gems/*/bin
into a colon-separated string of filenames (i.e. PATH compatible) matching the pattern?
i.e. echo /var/lib/gems/*/bin will return
/var/lib/gems/1.8/bin /var/lib/gems/1.9.1/bin
I want
/var/lib/gems/1.8/bin:/var/lib/gems/1.9.1/bin
instead.
The obvious approach is simply to replace the space character with ':' via tr, but that doesn't work if the filename itself contains the space character.
No need to mess with IFS, zsh can join arrays with a simple variable flag:
dirs=(/var/lib/gems/*/bin(N))
dirs=${(j.:.)dirs}
The (N) on the first line suppresses a warning if there are no files; the (j.:.) joins the array with :s. Works with 0, 1, or multiple matches.
without saving IFS and command substitution
dirs=(/var/lib/gems/*/bin) ; IFS=: eval 'dirs="${dirs[*]}"'
Another oneliner: printf "%s\n" /var/lib/gems/*/bin | paste -s -d':'
But @timo's answer is better in my opinion.