Made more portable by using grep -E

README.md

@@ -4,8 +4,9 @@ ls zero bash polyfill
 allows you to simulate the --zero option of ls from
 gnu coreutils v9, in earlier versions
 
-relies on coreutils (ls and tr), and grep with
-the -P option
+also works with bsdgrep, for usage on bsd and mac
+
+relies on coreutils (ls and tr), and grep
 
 simply source ls_zero.bash in your .bashrc,
-place it in /etc/profile.d, or similar
+place it in /etc/profile.d, or similar

ls_zero.bash

@@ -4,7 +4,7 @@ _ls() {
 }
 
 _lsp() {
-	printf "%s" "$*" | grep -qP '(\s|^)--zero(\s|$)'
+	printf "%s" "$*" | grep -qE '(^| )--zero( |$)'
 	local zero=$?
 	local args="$@"
 	declare -a args=(${args[@]/--zero/})