SVR5 and SCO OpenServer 5
linkblk(D4str)
linkblk --
STREAMS multiplexor link structure
Synopsis
#include <sys/stream.h>
#include <sys/ddi.h>
Description
The linkblk structure contains
the information needed by a multiplexing driver
to set up or take down a multiplexor link.
Usage
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.
Structure definitions
The linkblk structure contains the following members:
queue_t *l_qtop;
queue_t *l_qbot;
int l_index;
Structure members
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.
Hardware applicability
All
Version applicability
ddi:
1, 2, 3, 4, 5, 5mp, 6, 6mp, 7, 7mp, 8, 8mp
oddi:
1, 2, 2mp, 3, 3mp, 4, 4mp, 5, 5mp
References
datab(D4str),
Intro(D7str),
iocblk(D4str),
ioctl,
M_DATA(D7str),
M_IOCTL(D7str),
msgb(D4str),
qinit(D4str),
streamio,
streamtab(D4str)
19 June 2005
© 2005 The SCO Group, Inc. All rights reserved.
OpenServer 6 and UnixWare (SVR5) HDK - June 2005