Chapter 6
NI-FBUS Function Reference
NI-FBUS Hardware and Software User Manual
6-20
ni.com
nifOpenSession
Purpose
Returns a descriptor for an NI-FBUS Communications Manager session.
Format
nifError_t
nifOpenSession (
void *reserved,
nifDesc_t *out_ud)
Input
reserved
Reserved for future use. You must set this value to NULL.
Output
out_ud
A descriptor for the NI-FBUS Communications Manager
communications entity you request.
Context
Not applicable.
Description
nifOpenSession
returns a descriptor for the NI-FBUS Communications Manager session.
When you open a session, the NI-FBUS Communications Manager establishes a
communication channel between your application and the NI-FBUS entity. All subsequent
descriptors you open are associated with this session, and all the NI-FBUS calls on these
descriptors communicate with the NI-FBUS entity through the communication channel
established during the
nifOpenSession
call.
The
reserved
argument is reserved for future use. You must set
reserved
to NULL.
Return Values
E_OK
The call was successful.
E_SERVER_NOT_RESPONDING
Either the NI-FBUS Communications Manager server has not
been started or the server, in its current state, cannot respond to the
request.
E_RESOURCES
A system resource problem occurred. The resource problem is
usually a memory shortage or a failure of file access functions.