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+Pipeworks has an api that allows other mods to use its functionality.  
+Here is documented how to use the api.
+
+Note: This may be incomplete and can change at any time.  
+
+## Tube functions
+* `pipeworks.tube_inject_item(pos, start_pos, velocity, item, owner)`
+  * Injects an item into a tube.
+  * `owner` should be a playername but can be `nil`.
+  * Returns the newly added object.
+* `pipeworks.scan_for_tube_objects(pos)`
+* `pipeworks.notvel(possibilities, vel)`
+  * `possibilities` is a list of vectors.
+  * Returns the all entries `val` of `possibilities` where `val.x ~= -vel.x or val.y ~= -vel.y or val.z ~= -vel.z` in a new list.
+* `pipeworks.register_tube(name, def, ...)`
+* `pipeworks.after_dig(pos)`
+* `pipeworks.after_place(pos)`
+
+## Tube definition in node definition
+*(incomplete)*
+```lua
+tube = {
+	insert_object = func(pos, node, stack, direction, owner),
+	can_insert = func(pos, node, stack, direction, owner),
+	input_inventory = "main",
+	return_input_invref = func(pos, node, direction, player_name),
+	connect_sides = {left = 1, right = 1, back = 1, front = 1, bottom = 1, top = 1},
+	can_remove = func(frompos, fromnode, stack, dir, frominvname, spos),
+	remove_items(frompos, fromnode, stack, dir, count, frominvname, spos),
+}
+```
+
+## Pipe functions
+* `pipeworks.scan_for_pipe_objects(pos)`
+* `pipeworks.spigot_check(pos, node)`
+* `pipeworks.check_for_liquids(pos)`
+* `pipeworks.get_axis_dir(nodetable, pattern)`
+* `pipeworks.rotate_on_place(itemstack, placer, pointed_thing)`
+  * Can be used as `on_place` for pipe devices.
+* `pipeworks.scan_pipe_surroundings(pos)`
+* `pipeworks.check_for_inflows(pos,node)`
+* `pipeworks.fountainhead_check(pos,node)`
+* `pipeworks.look_for_stackable_tanks(pos)`
+* `pipeworks.fix_after_rotation(pos, node, user, mode, new_param2)`
+* `pipeworks.check_sources = function(pos,node)`
+
+## Helper functions
+* `pipeworks.load_position(pos)`
+* `pipeworks.vector_dot(a, b)`
+* `pipeworks.may_configure(pos, player)`
+* `pipeworks.facedir_to_right_dir(facedir)`
+* `pipeworks.facedir_to_top_dir(facedir)`
+* `pipeworks.table_contains(tbl, element)`
+* `pipeworks.vector_cross(a, b)`
+* `pipeworks.replace_name(tbl,tr,name)`
+  * *never used*
+* `pipeworks.fix_image_names(table, replacement)`
+  * *never used*
+* `pipeworks.table_recursive_replace(tbl, pattern, replace_with)`
+* `pipeworks.string_startswith(str, substr)`
+* `pipeworks.add_node_box(t, b)`
+  * *never used*
+* `pipeworks.table_extend(tbl, tbl2)`