as-atomic-operation

Purpose
Execute forms as an atomic operation.

Package   :portable-threads

Module   :portable-threads

Arguments and values

Returns
The primary value returned by evaluating the last form.

Description
This macro provides atomicity in the following entities: atomic-decf, atomic-delete, atomic-flush, atomic-incf, atomic-push, atomic-pushnew, and atomic-pop. It is intended only for implementing very brief atomic operations and should not be used for long computations or computations that wait or block.

Note that as-atomic-operation is only guaranteed to return a single value, not multiple values.

See also
    atomic-decf
    atomic-delete
    atomic-flush
    atomic-incf
    atomic-push
    atomic-pushnew
    atomic-pop

Example
Define an atomic nsorted-insert:

  (defun atomic-nsorted-insert (&rest args)
    (declare (dynamic-extent args))
    (as-atomic-operation (apply #'nsorted-insert args)))

as-atomic-operation