LispWorks User Guide and Reference Manual > 10 Storage Management > 10.5 Common Memory Management Features


10.5.6 Special actions

You may want to perform special actions when certain types of object are garbage collected, using the functions add-special-free-action, flag-special-free-action, flag-not-special-free-action and remove-special-free-action.

For example, when an open file stream is garbage collected, the file descriptor must be closed. This operation is performed as a special action.

LispWorks User Guide and Reference Manual - 22 Dec 2009