This parameter gives the address of the context data area in the user program that is to receive the saved user context. The contents of this area are completely user defined.

name: max_size

type: word unsigned

access: read only

mechanism: by reference

This gives the maximum size of the user context. If this parameter is not passed or is passed as zero, the number of bytes copied to the user context will be the same number of bytes that were last saved.

name: size

type: word unsigned

access: write only

mechanism: by reference

If this parameter is passed and is nonzero, the actual number of bytes copied to the user context is returned. This will never be greater than max_size.

Return Value:

FDB$_N ORMAL N ormal successful completion

FDB$_N OCON TEXT If no context has been saved for the specified stream

FDB$_TRUN CATED If the number of bytes last saved was greater than max_size

10.1.3.5 FDB_INIT

This routine initializes the database support code. It should be called exactly once during startup.

Calling Sequence:

FDB_IN IT [context_size], [save_context]

Arguments

name: context_size

type: word unsigned

access: read only

mechanism: by reference

This parameter gives the size in bytes of the user context. The effect of this parameter is to determine the size of the static area used to save stream contexts across runs. It can be approximate and is not used if save_context is not set.

Note: If save_context is TRUE, no addresses should be placed in the user context. There is no assurance that the memory will be mapped at the same address from one run to the next. If context_size is not passed, it defaults to 64.

name: save_context

type: boolean

access: read_only

mechanism: by reference

This parameter indicates whether the context of open database streams should be saved from one invocation of the database to the next. If it is FALSE or not specified, then no context will be saved from one run of the database to the next. If it is TRUE, then the context of currently active streams will be saved across runs.

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NDC comm CompuFax user manual Fdbinit, Fdbin IT contextsize, savecontext, Arguments