The makedev() function returns a formatted device number on success and NODEV on failure. The maj argument is the major number. The min argument is the minor number. The makedev() function can be used to create a device number for input to mknod(2).

The major() function returns the major number component from device.

The minor() function returns the minor number component from device.

Upon successful completion, makedev() returns a formatted device number. Otherwise, NODEV is returned and errno is set to indicate the error.

The makedev() function will fail if:

EINVAL

One or both of the arguments maj and min is too large, or the device number created from maj and min is NODEV.

The major() function will fail if:

EINVAL

The device argument is NODEV, or the major number component of device is too large.

The minor() function will fail if:

EINVAL

The device argument is NODEV.

See attributes(5) for descriptions of the following attributes:

mknod(2), stat(2), attributes(5)