ioconfig(4)						     Kernel Interfaces Manual						       ioconfig(4)

NAME

       ioconfig - ioconfig entry format

SYNOPSIS

DESCRIPTION

       The file is used to retain information on a system's I/O configuration across reboots.  It contains two types of information:

	 o  Mappings of dynamically allocated major numbers to drivers.

	 o  Mappings of instance numbers to hardware paths.

       At  boot  time this file is read and the information is stored in the kernel data structure.  The file is created by at install time and is
       modified by and when devices are added or removed (see insf(1M), rmsf(1M), and ioscan(1M)).  The only purpose of the file to maintain  con-
       figuration  information	when  the system is not running.  While the system is running, all accesses are made directly to the kernel struc-
       ture, although any tools that change the kernel structures must also keep consistent.

       There will be two copies of maintained: and A second copy is placed in because NFS diskless clients are not guaranteed to have  a  reliable
       directory at boot time.

       The file begins with the magic number.

       Following the magic number is an array of structures, which logically form a tree structure defining the connectivity of the various levels
       of software modules and managers, the device class and hardware address of each element, and the logical unit  associated  with	each  leaf
       node.  The root of the tree is array element 0.

       Each contains the following fields as defined in

       The definitions of each element are as follows:

       Each record must have a character string as its first entry
		 which	is  used to identify the record type.  The default record is the If the string begins with an underscore character then it
		 is one of the variants.

       This is the default record entry for the ioconfig file.
		 The must begin with an underscore character to distinguish record from other record type.

       The element is a structure that contains following elements.

       This record stores information about major numbers dynamically assigned
		 to drivers.  It is used to allow major number assignments to persist across boots.  The must begin with (underscore) character to
		 distinguish record from other record type.

       The contains following elements.

AUTHOR

       was developed by HP.

FILES

       SEE ALSO
	      insf(1M), ioinit(1M), ioscan(1M), rmsf(1M), magic(4).

																       ioconfig(4)