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.\"     @(#)sysline.1	6.6 (Berkeley) 4/24/91
.\"
.Dd April 24, 1991
.Dt SYSLINE 1
.Os BSD 4.2
.Sh NAME
.Nm sysline
.Nd display system status on status line of a terminal
.Sh SYNOPSIS
.Nm sysline
.Op Fl Dbcdehijlmpqrsw
.Op Fl H Ar remote
.Op Cm +N
.Sh DESCRIPTION
.Nm Sysline
runs in the background and periodically displays system status information
on the status line of the terminal.
Not all terminals contain a status line.
Those that do include the h19, concept 108, Ann Arbor Ambassador, vt100,
Televideo 925/950 and Freedom 100.
If no flags are given,
.Nm sysline
displays the time of day, the current load average, the change in load
average in the last 5 minutes, the number of users (followed by a `u'),
the number of runnable  process (followed by a `r')
.Bq Tn VAX No only ,
the number
of suspended processes (followed by a `s')
.Bq Tn VAX No only ,
and the users who have logged on and off since the last status report.
Finally, if new mail has arrived, a summary of it is printed.
If there is unread mail in your mailbox, an asterisk will appear after the
display of the number of users.
The display is normally in reverse video (if your terminal supports
this in the status line) and is right justified to reduce distraction.
Every fifth display is done in normal video to give the screen a chance
to rest.
.Pp
If you have a file named
.Pa .who
in your home directory, then the contents
of that file is printed first.  One common use of this
feature is to alias chdir, pushd, and popd  to place the current directory 
stack in
.Pa ~/.who
after it changes the new directory.
.Pp
The following flags may be given on the command line.
.Bl -tag -width Ds
.It Fl D
Print out the current day/date before the time.
.It Fl H Ar remote
Print the load average on the remote host
.Ar remote
.Bq Tn VAX No only .
If the host is down, or is not sending out
.Xr rwhod
packets, then
the down time is printed instead.  If the prefix "ucb" is present,
then it is removed.
.It Cm +N
Update the status line every N seconds. The default is 60 seconds.
.It Fl b
Beep once every half hour and twice every hour, just like those obnoxious
watches you keep hearing.
.It Fl c
Clear the status line for 5 seconds before each redisplay.
.It Fl d
Debug mode -- print status line data in human readable format.
.It Fl e
Print out only the information.  Do not print out the control commands
necessary to put the information on the bottom line.  This option is
useful for putting the output of
.Nm sysline
onto the mode line of an emacs window.
.It Fl h
Print out the host machine's name after the time
.Bq Tn VAX No only .
.It Fl i
Print out the process id of the
.Nm sysline
process onto standard output upon startup.
With this information you can send the alarm signal to the
.Nm sysline
process to cause it to update immediately.
.Nm Sysline
writes to the standard error, so you can redirect the standard
output into a file to catch the process id.
.It Fl j
Force the sysline output to be left justified even on terminals capable of
cursor movement on the status line.
.It Fl l
Don't print the names of people who log in and out.
.It Fl m
Don't check for mail. 
.It Fl p
Don't report the number of process which are runnable and suspended.
.It Fl q
Don't print out diagnostic messages if something goes wrong when starting up.
.It Fl r
Don't display in reverse video.
.It Fl s
Print "short" form of line by left-justifying
.Em iff
escapes are not allowed in the status line.
Some terminals (the Televideos and Freedom 100 for example)
do not allow cursor movement (or other "intelligent" operations)
in the status line.  For these terminals,
.Nm sysline
normally uses blanks to cause right-justification.
This flag will disable the adding of the blanks.
.It Fl w
Window mode -- print the status on the current line of the terminal,
suitable for use inside a one line window.
.El
.Pp
If you have a file
.Pa .syslinelock
in your home directory, then
.Nm sysline
will not update its statistics and write on your screen, it will just go to
sleep for a minute.  This is useful if you want to momentarily disable
.Nm sysline .
Note that it may take a few seconds from the time the lock file
is created until you are guaranteed that
.Nm sysline
will not write on the screen.
.Sh FILES
.Bl -tag -width /var/spool/rwho/whod.x -compact
.It Pa /var/run/utmp
names of people who are logged in
.It Pa /dev/kmem
contains process table
.Bq Tn VAX No only
.It Pa /var/spool/rwho/whod.*
who/uptime information for remote hosts
.Bq Tn VAX No only
.It Pa ${HOME}/.who
information to print on bottom line
.It Pa ${HOME}/.syslinelock
when it exists, sysline will not print
.El
.Sh BUGS
If you interrupt the display then you may find your cursor missing or 
stuck  on the status line.  The best thing to do is reset the terminal.
.Pp
If there is too much for one line, the excess is thrown away.
.Sh HISTORY
The
.Nm
command appeared in
.Bx 4.2 .
.Sh ENVIRONMENT
.Bl -tag -width HOME
.Nm Sysline
checks for the existence of
the following environment variables:
.It Ev HOME
The directory provided by the
.Ev HOME
variable is checked for the file
.Pa .who .
.It Ev TERM
Provides terminal type.
.It Ev USER
Provides username.
.El