prop_data(3) - NetBSD Manual Pages

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PROP_DATA(3)            NetBSD Library Functions Manual           PROP_DATA(3)


NAME
prop_data, prop_data_create_copy, prop_data_create_nocopy, prop_data_copy, prop_data_size, prop_data_value, prop_data_copy_value, prop_data_equals, prop_data_equals_data -- opaque data value property object
LIBRARY
Property Container Object Library (libprop, -lprop)
SYNOPSIS
#include <prop/proplib.h> prop_data_t prop_data_create_copy(const void *blob, size_t len); prop_data_t prop_data_create_nocopy(const void *blob, size_t len); prop_data_t prop_data_copy(prop_data_t data); const void * prop_data_value(prop_data_t data); bool prop_data_copy_value(prop_data_t data, void *buf, size_t buflen); size_t prop_data_size(prop_data_t data); bool prop_data_equals(prop_data_t dat1, prop_data_t dat2); bool prop_data_equals_data(prop_data_t data, const void *blob, size_t len);
DESCRIPTION
The prop_data family of functions operate on an opaque data value prop- erty object type. prop_data_create_copy(const void *blob, size_t len) Create a data object that contains a copy of blob with size len. Returns NULL on failure. prop_data_create_nocopy(const void *blob, size_t len) Similar to prop_data_create_copy(), but is allowed to not create aan internal copy of the opaque data, instead referencing the buffer passed by the caller. Caution must be exercised because data objects can have an indefinite lifespan. The caller must therefore ensure that the provided buffer reference will also be valid indefinitely. This is provided as a memory optimization; it is not guaranteed that the returned data object will reference the provided buffer, and thus callers should not rely on this behav- ior. Returns NULL on failure. prop_data_copy(prop_data_t data) Copy a data object. If the data object being copied is an exter- nal data reference, then the copy also references the same exter- nal data. Returns NULL on failure. prop_data_size(prop_data_t data) Returns the size of the data object. If the supplied object isn't a data object, zero is returned. prop_data_value(prop_data_t data) Returns a reference to the data object's buffer. If the supplied object isn't a data object or if the data container is empty, NULL is returned. prop_data_copy_value(prop_data_t data, void *buf, size_t buflen) Copies the contents of the data object into the supplied buffer of the specified size. Returns true if the copy succeeds and false iff the supplied buffer is not large enough or if the object is not a data object. prop_data_equals(prop_data_t dat1, prop_data_t dat2) Returns true if the two data objects are equivalent. If at least one of the supplied objects isn't a data object, false is returned. prop_data_equals_data(prop_data_t data, const void *blob, size_t len) Returns true if the data object's value is equivalent to blob with size len. If the supplied object isn't a data object, false is returned.
SEE ALSO
prop_array(3), prop_bool(3), prop_dictionary(3), prop_number(3), prop_object(3), prop_string(3), proplib(3)
HISTORY
The proplib(3) property container object library first appeared in NetBSD 4.0. Support for mutable data objects was deprecated in NetBSD 10.0. NetBSD 9.99 June 2, 2020 NetBSD 9.99
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