- Hewlett-Packard Printer User Guide

Using the VPO Application Programming Interfaces

Summary of VPO API Functions

Chapter 4192

Summary of VPO API Functions

Functions of the VPO Data API

Functions to Manipulate VPO Data Structures

See the man page opcdata_api(3) for information about these functions

and opcdata(3) for information about the VPO data-speciﬁc structures.

Table 4-3 Overview of the Data Access and Creation Functions

Function Call Description

opcdata_append_element() Appends a copy of the given element to the

container

opcdata_clear() Clears all ﬁelds in the container

opcdata_copy() Makes a copy of the speciﬁed opcdata structure

opcdata_copy_info_to_

actresp()

Copies components from a message or action

request to an action response

opcdata_create() Creates an empty data structure of type data_type

opcdata_delete_element() Deletes the element in the container and frees the

memory

opcdata_free() Deallocates previously allocated memory

opcdata_generate_id() Generates a VPO UUID

opcdata_get_cma() Gets the value of a speciﬁed custom message

attribute

opcdata_get_cmanames() Returns a list of all custom message attributes

available for a message

opcdata_get_double() Gets the double value of the speciﬁed attribute

opcdata_get_element() Makes a copy of the desired element

opcdata_get_error_msg() Returns the error description for the given error

code (thread-safe)