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kvar(8) [ultrix man page]

kvar(8) 						      System Manager's Manual							   kvar(8)

       kvar - modify RISC kernel variables in memory or on disk

       /usr/etc/kvar -r(b|w|l) [options] vmunix
       /usr/etc/kvar -w(b|w|l) [options] vmunix

       The  command  allows you to read or write RISC kernel variables, either in the on-disk image of or the active in-memory image.  The -r form
       of the command does variable reads; the -w form does variable writes.  The variable length qualifiers are:  b  (1  byte),  w  (word,  or  2
       bytes), and l (longword, or 4 bytes).

       Variable contents are displayed in hexadecimal format.

       -a address  Specifies  the  address  of	the  kernel  variable.	Either the -a or -s option must be specified.  The address is specified as
		   either a positive decimal or hexadecimal constant.

       -k	   Instructs to use the in-memory image of The default is to use the on-disk copy.

       -l	   Searches for a local symbol. The default is a global symbol search.

       -o offset   Adds an offset to the address (or address of the symbol name).  The offset value is specified as either a positive  decimal	or
		   hexadecimal constant.

       -s name	   Specifies the name of the kernel variable.

       -v value    Specifies  the  new value to be assigned by the -w form of The -v option is ignored if the -r form of is being used.  The value
		   is specified as either a positive decimal or hexadecimal constant.

       You must have appropriate file access permissions for (and for with the -k option).

       The command is available only on RISC systems.  For VAX systems, use to modify kernel variables.

       This example reads the variable `udpcksum' from the running kernel image:

	    % kvar -k -rl -s udpcksum /vmunix

       This example sets the `xyz' variable to zero in the running kernel image:

	      % kvar -k -wl -s xyz -v 0 /vmunix

       This example sets the variable `xyz' to -1 in the on-disk image of making this value persistent across reboots:

	      % kvar -wl -s xyz -v 0xffffffff /vmunix

       This example sets to zero 1 byte at offset 2 from address 0x80161a98 in the running kernel image:

	      % kvar -k -wb -o 2 -a 0x80161a98 /vmunix

See Also
       adb(1), dbx(1)

								       RISC								   kvar(8)

Check Out this Related Man Page

rarpd(8c)																 rarpd(8c)

       rarpd - reverse address resolution protocol (RARP) daemon

       /usr/etc/rarpd [ interface ] [ -v ] [ -n ] [ -f filename ]

       The daemon maps the Ethernet address of a machine to the machine's Internet Protocol (IP) address.

       When  is  invoked,  it  reads  the  file  (by  default) and waits to process a RARP request.  The file is checked every ten minutes for any
       changes.  If the file has been modified, reads it again. You can disable this feature with the option. You can force a scan of the file	by
       sending the daemon a SIGHUP signal.  See for more information on SIGHUP.

       The  format of the file is described in You can specify a file other than with the option.  The interface is the network interface on which
       the daemon should listen. The command shows the correct interface or interfaces for your system.  The daemon uses the  first  interface	it
       finds, if you do not specify an interface.  See the reference page for more information.

       Because	the  daemon has been implemented with the Ethernet Packet Filter (see you must configure your kernel with the packet filter option
       in order for to function properly.  The packet filter detects RARP broadcast packets and passes them to for processing. The filter priority
       for rarpd is set to 28.

       All messages from the daemon are directed to

       interface      Specifies the system's network interface.

       -v	      Causes  to  operate in verbose mode. This option logs details of RARP to The instance of a RARP request and its response are
		      also logged.

       -n	      Disables checking of the file.  By default, checks the file once every ten minutes, and, if the file was	modified,  rereads
		      the file.  If you specify the option scans the file once at startup time.

       -f filename    Reads an alternate Ethernet address file.

       The ignores all ARP requests sent encapsulated within a RARP packet. You should make all ARP request using the command.

       The machine for which an IP address is being requested must be present in the server's file.

       The following message is logged to if the Packet Filter is not configured in your kernel:
       Packet Filter is not configured in /vmunix
       The following messages are printed to your screen if the Packet Filter is not configured in your kernel:
       rarpd: cannot find symbol Pfilt_read in /vmunix
       option PACKETFILTER does not appear to be configured in
	      your kernel.

       Database that maps Ethernet addresses to hostnames

See Also
       ethers(3n), packetfilter(4), ethers(5), hosts(5), arp(8c), ifconfig(8c), syslog(8c)
       The Packet Filter: An Efficient Mechanism for User-Level Network Code

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