REGISTER_CHRDEV_REGI(9) Char devices REGISTER_CHRDEV_REGI(9)NAME
register_chrdev_region - register a range of device numbers
SYNOPSIS
int register_chrdev_region(dev_t from, unsigned count, const char * name);
ARGUMENTS
from
the first in the desired range of device numbers; must include the major number.
count
the number of consecutive device numbers required
name
the name of the device or driver.
DESCRIPTION
Return value is zero on success, a negative error code on failure.
COPYRIGHT Kernel Hackers Manual 2.6. July 2010 REGISTER_CHRDEV_REGI(9)
Check Out this Related Man Page
MAKEDEV(3) BSD Library Functions Manual MAKEDEV(3)NAME
makedev, major, minor -- device number conversion
SYNOPSIS
#include <sys/types.h>
dev_t
makedev(int major, int minor);
int
major(dev_t dev);
int
minor(dev_t dev);
DESCRIPTION
The makedev() macro allows a unique device number to be generated based on its major and minor number. The major() and minor() macros can be
used to obtain the original numbers from the device number dev.
In previous implementations of FreeBSD all block and character devices were uniquely identified by a pair of major and minor numbers. The
major number referred to a certain device class (e.g. disks, TTYs) while the minor number identified an instance within the device class.
Later versions of FreeBSD automatically generate a unique device number for each character device visible in /dev/. These numbers are not
divided in device classes.
On FreeBSD these macros are only used by utilities that need to exchange numbers with other operating systems that may use different encod-
ings for dev_t, but also applications that present these numbers to the user in a more conventional way.
RETURN VALUES
The major() macro returns a device major number that has a value between 0 and 255. The minor() macro returns a device minor number whose
value can span the complete range of an int.
SEE ALSO mknod(2), devname(3), devfs(5)BSD September 28, 2008 BSD