SCO OpenServer
emajor(D3oddi)
emajor, eminor --
extract extended major/minor device numbers
Synopsis
#include <sys/sysmacros.h>
int emajor(dev_t dev);
int eminor(dev_t dev);
Description
The emajor macro returns the external (real) major device
numbers associated with device type, dev.
The eminor macro returns the external (real) minor device
numbers associated with device type, dev.
Arguments
dev-
device number of type dev_t
that contains both the major and minor device numbers.
Return values
emajor returns the external major device number,
while eminor returns the external minor device number.
Usage
The
major(D3oddi),
makedev(D3oddi),
and
minor(D3oddi)
functions support extended minor device numbers
(minor numbers greater than 255).
The base major device number
and extended minor device number for a device
have a one-to-one correspondence with
the real (external) major and minor device numbers
(defined in
mdevice(F)).
This effectively removes the former limit on the number of devices
that a device driver can allocate to an adapter.
The -M option to
configure(ADM)
allows you to state the maximum and minimum number of devices that
can be specified in the
sdevice(F)
file; and, using the
-X option, is the command used to add or delete extended
minor device numbers from the mdevice file.
Context and synchronization
All
contexts.
Hardware applicability
All
Version applicability
oddi:
3, 3mp, 4, 4mp, 5, 5mp, 6, 6mp
SVR5 DDI compatibility
DDI drivers do not support these functions.
For DDI versions prior to version 8,
use the
getemajor(D3)
function in place of
emajor( )
and the
geteminor(D3)
function in place of
eminor( ).
DDI 8 and later versions
use the channel and instance number
rather than major and minor numbers. See
``Channel number'' in HDK Technical Reference,
``Device instance'' in HDK Technical Reference,
and
``Device number'' in HDK Technical Reference
for more information.
References
configure(ADM)
major(D3oddi),
makedev(D3oddi),
mdevice(F) ,
minor(D3oddi),
sdevice(F)
``Major and minor numbers'' in HDK Technical Reference
19 June 2005
© 2005 The SCO Group, Inc. All rights reserved.
OpenServer 5 HDK - June 2005