MAKEDEV(3)

MAKEDEV(3) | 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.

All block and character devices are uniquely identified by a pair of major and minor numbers. The major number refers to a certain device class (e.g. disks, TTYs) while the minor number identifies an instance within the device class.

# 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), MAKEDEV(8)

April 1, 2011 | NetBSD 11.0