with-out-parameters ( c-types quot -- values... )

Vocabulary
alien.data

Inputs and outputs

c-types	a list of scoped allocation specifiers
quot	a quotation
values...	zero or more values

Word description
Allocates values on the call stack, calls the quotation, then copies all stack allocated values to the data heap after the quotation returns.

A scoped allocation specifier is either:

•	a C type name,
•	or a triple with shape { c-type initial: initial }, where c-type is a C type name and initial is a literal value.

If no initial value is specified, the contents of the allocated memory are undefined.

Warning
Reading or writing a scoped allocation buffer outside of the given quotation will cause memory corruption.

Definition

USING: alien.data.private kernel ;

IN: alien.data

: with-out-parameters ( c-types quot -- values... )
    [ drop (local-allots) ] [ swap out-parameters ] 2bi
    (cleanup-allot) ; inline