bash: extracting last two dirs for a pathname

Question

I seem to have failed at something pretty simple, in bash. I have a string variable that holds the full path to a directory. I\'d like to assign the last two di

Answer 1

I prefer to use the builtins as much as I can, to avoid create unnecessary processes. Because your script may be run under Cygwin or other OS whose process creation are very expensive.

I think it's not so lengthy if you just want to extract two dirs:

base1="${DIRNAME##*/}"
dir1="${DIRNAME%/*}"
DIRNAME2="${dir1##*/}/$base1"

This can also avoid special char problems involved in executing another commands.