+export PATH TRIPEDIR
+
+# --- Check it will work, or at least stands a fighting chance ---
+#
+# Having loads of different tunnel types doesn't help any.
+
+test -x $tripe -a -x $tripectl || exit 0
+
+case `$tripe --tunnel` in
+ linux)
+ case `uname -s` in
+ Linux)
+ if { test -f /proc/misc && grep -q net/tun /proc/misc; } ||
+ modprobe -q tun; then
+ : good
+ else
+ echo >&2 "$tripe needs the Linux TUN/TAP driver to run."
+ exit 1
+ fi
+ if test -c /dev/net/tun; then
+ : good
+ else
+ echo >&2 "$tripe needs /dev/net/tun, which is missing."
+ exit 1
+ fi
+ ;;
+ *)
+ echo >&2 "CONFIGURATION ERROR"
+ echo >&2 " $tripe is compiled to use a Linux tunnel device, but"
+ echo >&2 " this system is `uname -s`"
+ exit 1
+ ;;
+ esac
+ ;;
+ unet)
+ case `uname -s` in
+ Linux)
+ if { test -f /proc/devices && grep -q unet /proc/devices; } ||
+ modprobe -q unet; then
+ : good
+ else
+ echo >&2 "$tripe needs the Linux UNET driver to run."
+ exit 1
+ fi
+ if test -c /dev/unet; then
+ : good
+ else
+ echo >&2 "$tripe needs /dev/unet, which is missing."
+ exit 1
+ fi
+ ;;
+ *)
+ echo >&2 "CONFIGURATION ERROR"
+ echo >&2 " $tripe is compiled to use a Linux tunnel device, but"
+ echo >&2 " this system is `uname -s`"
+ exit 1
+ ;;
+ esac
+ ;;
+ bsd)
+ case `uname -s` in
+ *BSD)
+ # Don't know how to check the device is working.
+ if test -c /dev/tun0; then
+ : good
+ else
+ echo >&2 "$tripe needs /dev/tun0, which is missing."
+ exit 1
+ fi
+ ;;
+ *)
+ echo >&2 "CONFIGURATION ERROR"
+ echo >&2 " $tripe is compiled to use a BSD tunnel device, but"
+ echo >&2 " this system is `uname -s`"
+ exit 1
+ ;;
+ esac
+ ;;
+esac
+
+# --- Do what was wanted ---