get external minor device number
Synopsis (Not in current DDI version)
minor_t geteminor(dev_t dev);
geteminor returns the external minor number
given a device number, dev.
External device number.
The external minor number.
External minor numbers are visible to the user.
Internal minor numbers are only visible in the kernel.
Since, on some architectures,
a driver can support more than one external major device
that maps to the same internal major device,
the kernel keeps a mapping between external minor numbers
and internal minor numbers to allow drivers to index arrays more easily.
For example, a driver may support two devices, each with five minor numbers.
The user may see each set of minor numbers numbered from zero to four,
but the driver sees them as one set of minor numbers numbered from zero to nine.
All driver entry points are passed device numbers using external minor numbers.
Systems that map external major device numbers one-to-one with internal
major numbers also map external minor numbers one-to-one with internal minor numbers.
Context and synchronization
1, 2, 3, 4, 5, 5mp, 6, 6mp, 7, 7mp, 7.1, 7.1mp
Differences between versions
is not supported in DDI 8;
drivers can access similar information
through the resmgr key and channel number. See
``Device number'' in HDK Technical Reference.
19 June 2005
© 2005 The SCO Group, Inc. All rights reserved.
OpenServer 6 and UnixWare (SVR5) HDK - June 2005