NDC comm CompuFax - Manual (Page 106)

8 2
This is the address of an optional AST procedure to execute when a request is received. If this parameter is
not passed or is passed as zero, FDB_GET operates synchronously. Therefore it does not return until a
request is received. If an AST routine is passed, FDB_GET returns as soon as the operation is begun and the
AST is delivered when a request is received.
name: astprm
type: longword
access: read only
mechanism: by value
This value is passed to the user's AST routine when the AST is delivered. It is not otherwise used and may be
anything the user desires. If the AST is not specified this parameter is ignored. If the AST is passed and this
parameter is not specified, then the AST routine is called with zero as the parameter.
Return Value:
The VMS status of the operation. If the operation is synchronous, this is the completion status. Otherwise, it
is the status of initiating the operation. If the server has shut down since the last GET operation and an AST
routine was specified, then the function return value will be normal and the completion status argument will
be set to FDB$_SERDOWN.
If a stream is being closed by the originator (meaning no more lookup requests will be issued for it) this
function returns FDB$_CLOSE (a success status). In this case, the user should perform any cleanup
necessary, then call FDB_CLOSE to allow FDB to deallocate internal context. If FDB$_CLOSE is returned,
the only output parameters that are valid are the stream ID and the status.
For success the completion status will be FDB$_NEWSTREAM if this database stream was not previously
open or FDB$_NORMAL if the stream was already active. Note: If context is being saved across runs (see
FDB_INIT) it is possible that streams may be in progress that are no longer valid. These streams may be
flushed out by returning FDB$_CLOSE for these streams during the initial calls to FDB_GET until all such
streams have been closed.
10.1.3.4 FDB_GET_CONTEXT
This is a function which returns the user context associated with a given database stream. This context must
have been previously saved with FDB_SAVE_CONTEXT. This function would normally be used if
program context is being saved across runs (see FDB_INIT.) It may also be used if context is not being saved
as a convenient way of keeping track of multiple streams. Generally the user context for a stream is saved
after processing a lookup request. Then before processing the next lookup request, it may be retrieved with
this function.
Calling Sequence:
FDB_GET_CON TEXT stream_id, context [, max_size [, size]]
Arguments
name: stream_id
type: longword signed
access: read only
mechanism: by reference
The identifier of the stream for which context is to be retrieved.
name: context
type: userdefined
access: write only
mechanism: by reference