GETMAJOR(9F) Kernel Functions for Drivers GETMAJOR(9F)

NAME

getmajor - get major device number

SYNOPSIS

#include <sys/types.h>
#include <sys/mkdev.h>
#include <sys/ddi.h>


major_t getmajor(dev_t dev);

INTERFACE LEVEL

Architecture independent level 1 (DDI/DKI).

PARAMETERS

dev
Device number.

DESCRIPTION

The getmajor() function extracts the major number from a device number.

RETURN VALUES

The major number.

CONTEXT

The getmajor() function can be called from user, interrupt, or kernel
context.

EXAMPLES

Example 1: Using getmajor()

The following example shows both the getmajor() and getminor(9F)
functions used in a debug cmn_err(9F) statement to return the major and
minor numbers for the device supported by the driver.


dev_t dev;

#ifdef DEBUG
cmn_err(CE_NOTE,"Driver Started. Major# = %d,
Minor# = %d", getmajor(dev), getminor(dev));
#endif

SEE ALSO

cmn_err(9F), getminor(9F), makedevice(9F)


Writing Device Drivers

WARNINGS

No validity checking is performed. If dev is invalid, an invalid number
is returned.

January 16, 2006 GETMAJOR(9F)