--- /dev/null
+// -*- mode:doc; -*-
+// vim: set syntax=asciidoc:
+
+[[makedev-syntax]]
+== Makedev syntax documentation
+
+The makedev syntax is used in several places in Buildroot to
+define changes to be made for permissions, or which device files to
+create and how to create them, in order to avoid calls to mknod.
+
+This syntax is derived from the makedev utility, and more complete
+documentation can be found in the +package/makedevs/README+ file.
+
+It takes the form of a space separated list of fields, one file per
+line; the fields are:
+
+|===========================================================
+|name |type |mode |uid |gid |major |minor |start |inc |count
+|===========================================================
+
+There are a few non-trivial blocks:
+
+- +name+ is the path to the file you want to create/modify
+- +type+ is the type of the file, being one of:
+ * f: a regular file
+ * d: a directory
+ * r: a directory recursively
+ * c: a character device file
+ * b: a block device file
+ * p: a named pipe
+- +mode+, +uid+ and +gid+ are the usual permissions settings
+- +major+ and +minor+ are here for device files - set to - for other
+ files
+- +start+, +inc+ and +count+ are for when you want to create a batch
+ of files, and can be reduced to a loop, beginning at +start+,
+ incrementing its counter by +inc+ until it reaches +count+
+
+Let's say you want to change the permissions of a given file; using
+this syntax, you will need to put:
+
+----
+/usr/bin/foobar f 644 0 0 - - - - -
+----
+
+Alternatively, if you want to change owner/permission of a directory
+recursively, you can put:
+
+----
+/usr/share/myapp r 750 myuser myuser - - - - -
+----
+
+On the other hand, if you want to create the device file +/dev/hda+
+and the corresponding 15 files for the partitions, you will need for
++/dev/hda+:
+
+----
+/dev/hda b 640 0 0 3 0 0 0 -
+----
+
+and then for device files corresponding to the partitions of
++/dev/hda+, +/dev/hdaX+, +X+ ranging from 1 to 15:
+
+----
+/dev/hda b 640 0 0 3 1 1 1 15
+----
+