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

NAME

       rwhod - The system status server

SYNOPSIS

       rwhod [-b|-l]

FLAGS

       Sets  the broadcast only mode.  Sends outgoing rwho packets, but ignores incoming ones.	Sets the listen only mode.  Collects incoming rwho
       packets from the network, but does not broadcast rwho data.

DESCRIPTION

       The rwhod daemon is the server that maintains the database used by the rwho(1) and ruptime(1) programs.	Its operation is predicated on the
       ability to broadcast messages on a network.

       The rwhod server operates as both a producer and consumer of status information.  As a producer of information, it periodically queries the
       state of the system and constructs status messages, which are broadcast on a network.  As a consumer of information, it listens	for  other
       rwhod servers' status messages, validating them, then recording them in a collection of files located in the /var/rwho directory.

       The server transmits and receives messages at the port indicated in the rwho service specification; see services(4).  The messages sent and
       received, are of the form: struct  outmp {
	       char    out_line[8];	       /* tty name */
	       char    out_name[8];	       /* user id */
	       long    out_time;	       /* time on */ };

       struct  whod {
	       char    wd_vers;
	       char    wd_type;
	       char    wd_fill[2];
	       int     wd_sendtime;
	       int     wd_recvtime;
	       char    wd_hostname[32];
	       int     wd_loadav[3];
	       int     wd_boottime;
	       struct  whoent {
		       struct  outmp we_utmp;
		       int     we_idle;
	       } wd_we[1024 / sizeof (struct whoent)]; };

       All fields are converted to network byte order prior to transmission.  The load averages are as calculated by the w(1) program, and  repre-
       sent  load  averages over the 5-, 10-, and 15-minute intervals prior to a server's transmission; they are multiplied by 100 for representa-
       tion in an integer.  The hostname included is that returned by the gethostname(2) system call, with any trailing domain name omitted.   The
       array  at the end of the message contains information about the users logged in to the sending machine.	This information includes the con-
       tents of the utmp(4) entry for each nonidle terminal line and a value indicating the time in seconds since a character was last received on
       the terminal line.

       Messages  received  by  the rwho server are discarded unless they originated at an rwho server's port.  In addition, if the host's name, as
       specified in the message, contains any unprintable ASCII characters, the message is discarded.  Valid messages received by rwhod are placed
       in  files  named  whod.hostname	in  the  /var/rwho  directory.	These files contain only the most recent message, in the format previously
       described.

       Status messages are generated approximately once every 3 minutes.  rwhod performs an nlist(3) on /vmunix every 30 minutes to guard  against
       the possibility that this file is not the system image currently operating.

FILES

       Specifies the command path

RELATED INFORMATION

       Commands: rwho(1), ruptime(1) delim off

																	  rwhod(8)