The function
set-memory-exhausted-callback
adds a callback that is called when memory is exhausted. That is, when the system fails to map memory.
Note: set-memory-check is a more robust way to protect against memory exhaustion problems.
If function is a function designator then it should be a function with signature
function gen-num size type-name static
function is expected to report what the system was trying to allocate when it failed to map memory. Its arguments are:
The number of the generation in which it was trying to allocate.
The size in bytes which it was trying to allocate.
A string naming the allocation type it was trying to allocate.
A boolean, true if it was trying to allocate a static object, and false otherwise.
function
can also have the special value
:reset
, which resets the callback list to
nil
.
function
can also be
nil
, which means do nothing but simply return the current list of callbacks.
where defines the position in the list that the callback function is placed. Its allowed values are:
function is placed first in the callbacks list.
function is placed last in the callbacks list.
function is removed from the callbacks list.
set-memory-exhausted-callback
always first removes
function
from the callbacks list, and then adds it according to
where
. The default value of
where
is
:first
. Functions in the list are compared with
equalp
.
set-memory-exhausted-callback
returns the callback list.
When a callback is called, Lisp already failed to map memory. This means that you must not rely on the callback to do real work. It should therefore attempt only a minimal amount of work such as clean-ups and generating debug information. It should not try to do real work.
After all the callbacks are called, the system signals an error of type storage-exhausted. The condition can be accessed using the accessors described for storage-exhausted.
Note: this function is implemented only in 64-bit LispWorks. It is not relevant to the Memory Management API in 32-bit implementations.