NAME | SYNOPSIS | DESCRIPTION | CONFORMING TO | NOTES | SEE ALSO | COLOPHON
MAKEDEV(3) Linux Programmer's Manual MAKEDEV(3)
makedev, major, minor - manage a device number
#define _BSD_SOURCE
#include <sys/types.h>
dev_t makedev(int maj, int min);
int major(dev_t dev);
int minor(dev_t dev);
A device ID consists of two parts: a major ID, identifying the class of the
device, and a minor ID, identifying a specific instance of a device in that
class. A device ID is represented using the type dev_t.
Given major and minor device IDs, makedev() combines these to produce a device
ID, returned as the function result. This device ID can be given to mknod(2),
for example.
The major() and minor() functions perform the converse task: given a device
ID, they return, respectively, the major and minor components. These macros
can be useful to, for example, decompose the device IDs in the structure
returned by stat(2).
The makedev() major() and minor() functions are not specified in POSIX.1, but
are present on many other systems.
These interfaces are defined as macros. Since glibc 2.3.3, they have been
aliases for three GNU-specific functions: gnu_dev_makedev(3),
gnu_dev_major(3), and gnu_dev_minor(3). The latter names are exported, but
the traditional names are more portable.
mknod(2), stat(2)
This page is part of release 3.23 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can be found
at http://www.kernel.org/doc/man-pages/.
Linux 2008-12-01 MAKEDEV(3)