alloc_chrdev_region(9) [suse man page]

ALLOC_CHRDEV_REGION(9)						   Char devices 					    ALLOC_CHRDEV_REGION(9)

NAME

       alloc_chrdev_region - register a range of char device numbers

SYNOPSIS

       int alloc_chrdev_region(dev_t * dev, unsigned baseminor, unsigned count, const char * name);

ARGUMENTS

       dev
	   output parameter for first assigned number

       baseminor
	   first of the requested range of minor numbers

       count
	   the number of minor numbers required

       name
	   the name of the associated device or driver

DESCRIPTION

       Allocates a range of char device numbers. The major number will be chosen dynamically, and returned (along with the first minor number) in
       dev. Returns zero or a negative error code.

COPYRIGHT

Kernel Hackers Manual 2.6.					     July 2010						    ALLOC_CHRDEV_REGION(9)

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