Question

I have a path that is managed by update-alternatives. It seems this is confusing bash.

The following if should not print yes. But it does because bash thinks the directory does not exist – when in fact it does. This is all done as root, and I’ve tried the single bracket versions.

RUBY_ROOT=/usr/bin/ruby
CHK_DIR_PATH=`readlink -f "${RUBY_ROOT}"`
if [[ ! -d "${CHK_DIR_PATH}" ]] ; then echo yes; fi

The path does exist:

ls -la ${CHK_DIR_PATH}
-rwxr-xr-x 1 root root 6993617 2011-06-21 15:37 /usr/bin/ruby1.9.2-p180

Is there an alternative way to check if a directory does not exist?

Answer 1

The path exists, but it’s not a directory; according to your ls -l, it’s a file. So test -d correctly returns false, whereas test -e and test -f would return true. I suspect you have something installed incorrectly.