| MG Mud User | 88f1247 | 2016-06-24 23:31:02 +0200 | [diff] [blame^] | 1 | SYNOPSIS |
| 2 | int <lfun> (int refcount) |
| 3 | int <closure>(int ref, object ob) |
| 4 | |
| 5 | DESCRIPTION |
| 6 | The hook H_CLEAN_UP defines a lfun or a closure used to clean |
| 7 | up an object. In older drivers this was hardwired to the lfun |
| 8 | clean_up(). |
| 9 | |
| 10 | The function is applied by the driver when an object hasn't been |
| 11 | used for a long time, to give it a possibility to |
| 12 | self-destruct. The refcount <ref> passed as argument will be 0 for |
| 13 | clone objects, 1 for a simple loaded object, and greater when |
| 14 | the object is cloned or inherited by some existing object. It |
| 15 | is recommended not to self_destruct the object when the |
| 16 | reference count is greater than one. |
| 17 | |
| 18 | By convention, a refcount < 0 is used if some other object |
| 19 | asks the called object to clean_up. |
| 20 | |
| 21 | If the function is a closure, the second argument <ob> is the |
| 22 | object to clean up. |
| 23 | |
| 24 | If the hook specifies a non-existing lfun, or if the call |
| 25 | returns 0, no further attempt to clean up this object will be done. |
| 26 | |
| 27 | Returning a non-zero value is only recommended when the reason |
| 28 | why the object can't self-destruct is likely to vanish without |
| 29 | the object being touched, that is, when no local function is |
| 30 | called in it, (and in compat mode also when the object is not |
| 31 | being moved around). |
| 32 | |
| 33 | A typical mud configuration defines the time to wait for |
| 34 | clean_up() so long that you can assert reset() has been |
| 35 | called since the object has been touched last time. |
| 36 | |
| 37 | EXAMPLES |
| 38 | A clone of /std/drink defines clean_up() to self-destruct if |
| 39 | it is empty, not carried a living being and not touched for |
| 40 | a long time. |
| 41 | |
| 42 | A room that inherits /std/room defines clean_up() to |
| 43 | self-destruct if it is neither inherited nor used as a |
| 44 | blueprint, is empty and was not entered for a long time. |
| 45 | |
| 46 | HISTORY |
| 47 | Before 3.2.1, the function was hardwired to the lfun clean_up(). |
| 48 | |
| 49 | SEE ALSO |
| 50 | reset(A), heart_beat(A), call_out(E), destruct(E), remove(A), |
| 51 | hooks(C) |