NAME

malloc_create_zone, malloc_destroy_zone, malloc_default_zone, malloc_zone_from_ptr, malloc_zone_malloc, malloc_zone_calloc, malloc_zone_valloc, malloc_zone_realloc, malloc_zone_memalign, malloc_zone_free — zone-based memory allocation

SYNOPSIS

#include <malloc/malloc.h>

malloc_zone_t *
malloc_create_zone(vm_size_t start_size, unsigned flags);

void
malloc_destroy_zone(malloc_zone_t *zone);

malloc_zone_t *
malloc_default_zone(void);

malloc_zone_t *
malloc_zone_from_ptr(const void *ptr);

void *
malloc_zone_malloc(malloc_zone_t *zone, size_t size);

void *
malloc_zone_calloc(malloc_zone_t *zone, size_t num_items, size_t size);

void *
malloc_zone_valloc(malloc_zone_t *zone, size_t size);

void *
malloc_zone_realloc(malloc_zone_t *zone, void *ptr, size_t size);

void *
malloc_zone_memalign(malloc_zone_t *zone, size_t alignment, size_t size);

void
malloc_zone_free(malloc_zone_t *zone, void *ptr);

DESCRIPTION

The malloc_create_zone() function creates a malloc zone, advising an initial allocation of start_size bytes, and specifying flags The returned malloc zone can be used to provide custom allocation and deallocation behavior, and to retrieve additional information about the allocations in that zone. At present there are no client settable flag values recognized by malloc_create_zone(), the flags argument should always be passed as zero.

The malloc_destroy_zone() function deallocates all memory associated with objects in zone as well as zone itself.

The malloc_default_zone() function returns the default system malloc zone, used by malloc(3), and free(3).

The malloc_zone_from_ptr() function returns a pointer to the malloc zone which contains ptr or NULL, if the pointer does not point to an allocated object in any current malloc zone.

The malloc_zone_malloc(), malloc_zone_calloc(), malloc_zone_valloc(), malloc_zone_realloc(), malloc_zone_memalign(), and malloc_zone_free() perform the same task on zone as their non-prefixed variants, malloc(3), calloc(3), valloc(3), realloc(3), posix_memalign(3), and free(3) perform on the default system malloc zone.

RETURN VALUES

The malloc_create_zone(), malloc_default_zone(), and malloc_zone_from_ptr() functions return a pointer to a malloc_zone_t structure, or NULL if there was an error.

The malloc_zone_malloc(), malloc_zone_calloc(), malloc_zone_valloc(), malloc_zone_realloc(), and malloc_zone_memalign() functions return a pointer to allocated memory. If there is an error, they return a NULL pointer. They are not required to set errno.

SEE ALSO

malloc(3), posix_memalign(3)