Re: [PATCH 11/19] bash prompt: use bash builtins to find out current branch

SZEDER Gábor [off-list ref] writes:

'readlink' is not a bash builtin, so it would need the same number of
fork()s and exec() as 'symbolic-ref'.  Of course, the 'readlink'
binary is much smaller than git and has less to do, so it might be a
tiny bit faster, but for this rare corner case it really doesn't
matter.

Correct, and by not using it you do not have to worry about systems
that does not install the binary.