HP-UX SNAplus2 R7 NOF Programmer's Guide

ManualsBrandsHP ManualsSoftwareHP-UX SNAplus2 Software

Writing NOF Applications

Windows Considerations

• QUERY_CENTRAL_LOGGER

• For all other NOF verbs, the application supplies the value that was returned on the CONNECT_NODE

or OPEN_FILE verb.

nofvcb

Pointer to a Verb Control Block (VCB) that contains the parameters for the verb being issued. The VCB

structure for each verb is described in Chapter 3,

NOF API Verbs. These structures are deﬁned in the NOF

API header ﬁle nof_c.h.

Note

The NOF VCBs contain many parameters marked as “reserved”; some of these are

used internally by the SNAplus2 software, and others are not used in this version

but may be used in future versions. Your application must not attempt to access any

of these reserved parameters; instead, it must set the entire contents of the VCB to

zero to ensure that all of these parameters are zero, before it sets other parameters

that are used by the verb. This ensures that SNAplus2 will not misinterpret any of

its internally-used parameters, and also that your application will continue to work

with future SNAplus2 versions in which these parameters may be used to provide

new functions.

To set the VCB contents to zero, use memset:

memset(nofvcb, 0, sizeof(nofvcb));

Returned Values

The nof entry point does not have a return value. When the call returns, the application should examine the return

code in the VCB to determine whether the verb completed successfully and to determine parameters it needs for

further verbs. In particular, when the CONNECT_NODE or OPEN_FILE verb completes successfully, the VCB

contains the target_handle that the application should use when issuing subsequent verbs.

Using the Synchronous Entry Point

Only one synchronous verb can be outstanding at any time for each target handle. A synchronous verb fails with

the primary return code

AP_STATE_CHECK

and secondary return code AP_SYNC_PENDING

if another synchronous

verb for the same target handle is in progress.

Asynchronous Entry Point: nof_async

An application uses nof_async to issue a NOF verb asynchronously. The application also supplies a pointer to

a callback routine. SNAplus2 returns control to the application immediately with a returned value that indicates

whether verb processing is still in progress or has completed. In most cases, verb processing is still in progress

when control returns to the application. In these cases, SNAplus2 uses the application-supplied callback routine to

return the results of the verb processing at a later time. In some cases, verb processing is complete when SNAplus2

returns control to the application, so SNAplus2 does not use the application’s callback routine.

Function Call

AP_UINT16 WINAPI nof_async(

AP_UINT32 target_handle,

void * nofvcb,

NOF_CALLBACK (*comp_proc),

AP_CORR corr

);

typedef void (*NOF_CALLBACK) (

AP_UINT32 target_handle,

void * nofvcb,