minor − manage a device number
_BSD_SOURCE /* See feature_test_macros(7) */
makedev(unsigned int maj, unsigned int
unsigned 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.
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).
explanation of the terms used in this section, see
makedev(), major(), and minor()
functions are not specified in POSIX.1, but are present on
many other systems.
interfaces are defined as macros. Since glibc 2.3.3, they
have been aliases for three GNU-specific functions:
gnu_dev_makedev(), gnu_dev_major(), and
gnu_dev_minor(). The latter names are exported, but
the traditional names are more portable.
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