nvram(8)                                                 nvram(8)



NAME
       nvram - manipulate Open Firmware NVRAM variables

SYNOPSIS
       nvram [ -p ] [ -f filename ] [ name ] [= value ] ...

DESCRIPTION
       The  nvram  command  allows  manipulation of Open Firmware
       NVRAM variables.  It can be used to get or set a variable.
       It can also be used to print all of the variables or set a
       list of variables from a file.

       In principle, name can be any string.   In  practice,  not
       all  strings  will be accepted.  Old world machines have a
       fixed set of Open Firmware variables.  New World  machines
       can  create  new  variables  as  desired.   Some variables
       require administrator privilege to get or set.

       The given value must match  the  data  type  required  for
       name.   Binary  data  can  be  set using the %xx notation,
       where xx is the hex value of the byte.  The type  for  new
       variables is always binary data.

       Two  Open Firmware variables have special treatment on old
       world machines: boot-command and boot-args.   As  long  as
       boot-command starts with "# bootr," the boot-args variable
       will be present.  Getting or setting boot-args will get or
       set  the  boot-command while preserving the "# bootr".  In
       most cases when setting boot  arguments  for  the  kernel,
       there  is  no need to test for old world and set boot-com-
       mand.  Instead set boot-args with the desired arguments.

OPTIONS
       -p     Print all of the Open Firmware variables.

       -f filename
              Set Open Firmware variables from a text file.   The
              file  must be a list name=value statements.  If the
              last character of a line is \, the  value  will  be
              continued to the next line.

EXAMPLES
              example% nvram boot-args="-s rd=*hd:10"

       Set  the boot-args variable to "-s rd=*hd:10".  This would
       specify single user mode with  the  root  device  in  hard
       drive partition 10.

              example%   nvram  my-variable="String  One%00String
              Two%00%00"

       Create a new variable, my-variable, containing a  list  of
       two C-strings that is terminated by a NUL.

FILES
       /usr/share/nvram              Files containing patches for
                                     old world machines.



                        December 12, 2000                nvram(8)