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nvram(8)                                                                                            nvram(8)



NAME
       nvram - manipulate firmware NVRAM variables

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

DESCRIPTION
       The  nvram  command  allows manipulation of 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.
       Changes to NVRAM variables are only saved by clean restart or shutdown.

       In  principle,  name  can  be  any string.  In practice, not all strings will be accepted.  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.

OPTIONS
       -d name
              Deletes the named firmware variable.

       -f filename
              Set firmware variables from a text file.  The file must be a list of "name value"  statements.
              The  first space on each line is taken to be the separator between "name" and "value".  If the
              last character of a line is \, the value extends to the next line.

       -x     Use XML format for reading and writing variables.  This option must be used before the  -p  or
              -f options, since arguments are processed in order.

       -c     Delete all of the firmware variables.

       -p     Print all of the firmware variables.

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.

              example% nvram -d my-variable

       Deletes the variable named my-variable.



                                              October 28, 2003                                      nvram(8)