diff --git a/libexec/rbenv-init b/libexec/rbenv-init
index 29f7512a..dcb1bd5a 100755
--- a/libexec/rbenv-init
+++ b/libexec/rbenv-init
@@ -23,6 +23,7 @@ done
 shell="$1"
 if [ -z "$shell" ]; then
   shell="$(ps c -p $(ps -p $$ -o 'ppid=' 2>/dev/null) -o 'comm=' 2>/dev/null || true)"
+  shell="${shell##-}"
   shell="$(basename "${shell:-$SHELL}")"
 fi