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udi_buf_path_t(3udi)


Buffer path routing handle

SYNOPSIS

#include <udi.h>

typedef <HANDLE> udi_buf_path_t;
 
/* NULL buffer path handle constant */
 
#define  UDI_NULL_BUF_PATH				<NULL_HANDLE>
 

Description When a driver allocates a UDI buffer, it associates it with a buffer path. Buffer paths indicate intended destinations for data buffers, typically associated with the allocating driver's parent. Drivers refer to buffer paths via opaque buffer path handles.

Path handles are explicitly allocated (via udi_buf_path_alloc), or provided to a driver instance via a UDI_CHANNEL_BOUND channel event indication; the driver indicates how many path handles are needed on a per-parent basis and the environment provides that number of handles each time a parent is bound to the driver.

Buffer path handles are not transferable between regions.

Warnings Drivers must not compare handle values for equality, but the UDI_HANDLE_IS_NULL macro can be used to determine if a handle variable currently holds a null value.

references UDI_HANDLE_IS_NULL, udi_channel_event_ind, udi_buf_copy, udi_buf_write


UDI Core Specification Contents