#!/bin/sh
TMP=$(mktemp -p /dev/shm) &&
	{ TYPE=$(curl -sL -w "%{content_type}\n" $@ -o "$TMP") && case "$TYPE" in
		application/pdf) zathura "$TMP";;
		image/*) sxiv "$TMP";;
		text/*) less "$TMP";;
		*) hexdump "$TMP";;
	esac }
rm -f "$TMP"