Copyright (c) 2008 Linux Foundation, written by Michael Kerrisk <firstname.lastname@example.org> %%%LICENSE_START(VERBATIM) Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permissi...
NAMEmakedev, major, minor - manage a device number
#define _BSD_SOURCE /* See feature_test_macros(7) */ #include <sys/types.h> dev_t makedev(unsigned int maj, unsigned int min); unsigned int major(dev_t dev); unsigned int minor(dev_t dev);
DESCRIPTIONA 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).
ATTRIBUTESFor an explanation of the terms used in this section, see attributes(7).
|makedev(), major(), minor()||Thread safety||MT-Safe|