Using the HP-UX IPQoS API

Using Sessions

Using Sessions

Every application that uses the HP-UX IPQoS API must use the context of a session. The session-related functions that are part of the API include functions to initiate and set the type of session, get the session type and terminate the session. Once in a session, the application can: configure HP-UX IPQoS filters and policies, read the current HP-UX IPQoS configuration, or obtain HP-UX IPQoS statistics.

Starting a Session

Every application that uses the HP-UX IPQoS API must start a session by calling the function:

uint32_t IpqosInitSession(uint32_t version,char * configName,IpqosSessionType sessionType)

The arguments can be described as follows:

—version: the version ID of the HP-UX IPQoS API (this is a #defined constant in the HP-UX IPQoS header file, in this release it is IPQOS_API_VERSION_ID_1). The version ID scheme allows for the detection of API-application mismatch.

—configName: specify NULL (this argument is for future enhancements and is currently unused).

—sessionType: specify the type of session being started. Permitted session types are:

IPQOS_SESSION_CONFIG, IPQOS_SESSION_READ, IPQOS_SESSION_STATS.

A return value of IPQOS_S_SUCCESS indicates the session started successfully. Any other return value signifies an error.

When any session type is started, the API first reads the current HP-UX IPQoS configuration stored in the HP-UX IPQoS database. It forms a list of HP-UX IPQoS adapters, where each adapter contains a list of attached HP-UX IPQoS policies, and where each HP-UX IPQoS policy contains a list of attached HP-UX IPQoS filters. It also communicates with the HP-UX IPQoS kernel module.

An application can only have one active session (of any type) at a given time. Thus, to start a new session, the current session (if one exists) must first be terminated. The functions available to terminate a session are discussed in a following section.

Session Types

There are three session types in the HP-UX IPQoS API:

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Chapter 2