Add a URL for reference.
# Of course, it might be easier to avoid messing with envars by just
# editing the script before executing it.
#
+# https://amoffat.github.io/sh/sections/special_arguments.html
+#
{ IFS= read -r header ; { printf "%s\n" "$header" >&${FS1} ; } ; IFS= read -r -u${FS2} options; printf "%s\n" "$header" ; sort $options ; }
