NAME
        CloseIFF -- close an IFF context. (V36)

   SYNOPSIS
        CloseIFF(iff);
                 A0

        VOID CloseIFF(struct iffhandle *);

   FUNCTION
        Completes an IFF read or write operation by closing the IFF context
        established for this iffhandle structure. the iffhandle structure
        itself is left ready for re-use and a new context can be opened with
        openiff(). this function can be used for cleanup if a read or write
        fails partway through.

        As part of its cleanup operation, CloseIFF() calls the client-
        supplied stream hook vector. The iffstreamcmd packet will be set
        as follows:

                sc_Command:     IFFCMD_CLEANUP
                sc_Buf:         (Not applicable)
                sc_NBytes:      (Not applicable)

        This operation is NOT permitted to fail;  any error code returned
        will be ignored (best to return 0, though). DO NOT write to this
        structure.

   INPUTS
        iff - pointer to iffhandle structure previously opened with
              openiff(). starting with v39, this may be null.

   SEE ALSO
        openiff(), initiff(), <libraries/iffparse.h>