SVR5 and SCO OpenServer 5

linkblk(D4str)

linkblk -- STREAMS multiplexor link structure

Synopsis

   #include <sys/stream.h>
   #include <sys/ddi.h>

The linkblk structure contains the information needed by a multiplexing driver to set up or take down a multiplexor link.

The linkblk structure is embedded in the M_DATA(D7str) portion of the M_IOCTL(D7str) messages generated from the following streamio calls: I_LINK, I_UNLINK, I_PLINK, I_PUNLINK.

The linkblk structure contains the following members:

   queue_t	*l_qtop;
   queue_t	*l_qbot;
   int	l_index;

l_qtop: pointer to the lowest write queue in the upper stream. In other words, it is the write queue of the multiplexing driver. If the link is persistent across closes of the driver, then this member is set to NULL.
l_qbot: pointer to the upper write queue in the lower stream. The lower stream is the stream being linked under the multiplexor. The topmost read and write queues in the lower stream are given to the multiplexing driver to use for the lower half of its multiplexor processing. The qinit(D4str) structures associated with these queues are those specified for the lower processing in the multiplexing driver's streamtab(D4str) structure.
l_index: unique ID that identifies the multiplexing link in the system. The driver can use this as a key on which it can multiplex or de-multiplex.

All

ddi: 1, 2, 3, 4, 5, 5mp, 6, 6mp, 7, 7mp, 8, 8mp
oddi: 1, 2, 2mp, 3, 3mp, 4, 4mp, 5, 5mp