File Formats                                      pathtoinst(4)



NAME
     pathtoinst - device instance number file

SYNOPSIS
     /etc/pathtoinst


DESCRIPTION
     /etc/pathtoinst records mappings of physical device  names
     to instance numbers.


     The instance number of a device  is  encoded  in  its  minor
     number, and is the way that a device driver determines which
     of the possible devices that it may drive is referred to  by
     a given special file.


     In order to keep instance numbers persistent across reboots,
     the system records them in /etc/pathtoinst.


     This file is read only at  boot  time,  and  is  updated  by
     adddrv(1M) and devfsadm(1M).


     Note that it is  generally  not  necessary  for  the  system
     administrator  to change this file, as the system will main-
     tain it.


     The  system  administrator  can  change  the  assignment  of
     instance  numbers  by editing this file and doing a reconfi-
     guration reboot. However, any changes made in this file will
     be  lost  if  adddrv(1M)  or devfsadm(1M) is run before the
     system is rebooted.


     Each instance entry is a single line of the form:

       "physical name" instance number "driver binding name"



     where

     physical name          is the absolute physical pathname  of
                            a   device.  This  pathname  must  be
                            enclosed in double quotes.






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File Formats                                      pathtoinst(4)



     instance number        is a decimal or hexadecimal number.


     driver binding name    is the name  used  to  determine  the
                            driver  for the device. This name may
                            be a driver alias or a  driver  name.
                            The   driver  binding  name  must  be
                            enclosed in double quotes.


EXAMPLES
     Example 1 Sample pathtoinst Entries


     Here are some sample pathtoinst entries:


       "/iommu@f,e0000000" 0 "iommu"
       "/iommu@f,e0000000/sbus@f,e0001000" 0 "sbus"
       "/iommu@f,e0000000/sbus@f,e0001000/sbusmem@e,0" 14 "sbusmem"
       "/iommu@f,e0000000/sbus@f,e0001000/sbusmem@f,0" 15 "sbusmem"
       "/iommu@f,e0000000/sbus@f,e0001000/ledma@f,400010" 0 "ledma"
       "/obio/serial@0,100000" 0 "zs"
       "/SUNW,sx@f,80000000" 0 "SUNW,sx"



FILES
     /etc/pathtoinst    Mapping of  physical  device  names  to
                          instance numbers.


SEE ALSO
     adddrv(1M), boot(1M), devfsadm(1M), mknod(1M)

WARNINGS
     If the file is removed the system may not be bootable (as it
     may rely on information found in this file to find the root,
     usr or swap device). If it does successfully boot,  it  will
     regenerate  the file, but after rebooting devices may end up
     having different minor numbers than  they  did  before,  and
     special  files  created via mknod(1M) may refer to different
     devices than expected.


     For the same reasons, changes should not  be  made  to  this
     file without careful consideration.

NOTES
     This document does not constitute an API.  pathtoinst  may
     not  exist or may have a different content or interpretation
     in a future release. The existence of this notice  does  not



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File Formats                                      pathtoinst(4)



     imply  that  any  other documentation that lacks this notice
     constitutes an API.





















































SunOS 5.11          Last change: 18 May 2007                    3