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libcache(3)              BSD Library Functions Manual              libcache(3)

NAME
     libcache -- the caching framework

SYNOPSIS
     #include <cache.h>

DESCRIPTION
     The libcache framework provides a facility for creating in memory data caches.  Each cache is a mutable
     dictionary that associates values with their keys.  A cache limits the number of values it keeps
     according to available system memory and selects values to evict when the limit is exceeded.  Recently
     and frequently used values are less likely to be selected for eviction.

     Cache keys and values should be cast as pointers.  The framework provides a callback interface for sup-porting supporting
     porting arbitrary types of keys and values and implements callback functions for common types.  See
     cache_callbacks(3) for more information.

     Clients retrieve a value previously added to a cache using the value's key.  When the client gets a
     value, the cache increments a reference count on the value.  When the client finishes with a value
     retrieved from a cache they must release the value back to the cache.  Referenced values are considered
     in use and will not be evicted.  The cache may evict unreferenced values (e.g. to make room for other
     values or reduce its size).

     The number of values allowed in a cache at one time is managed by the cache framework.  Cache size will
     grow when the system has available memory and shrink under memory pressure.

     Libcache is thread-safe.  It is not safe to call back into the cache API from cache callback functions.

SEE ALSO
     cache_create(3), cache_set_and_retain(3)

Darwin                            May 7, 2009                           Darwin