SPLITVT(1) NONESSENTIAL UTILITIES SPLITVT(1)NAMEsplitvt - run two shells in a split window
SYNOPSISsplitvt [options] [shell]
OPTIONS-upper command
Runs 'command' in the upper window
-lower command
Runs 'command' in the lower window
-s numlines
Sets 'numlines' to the number of lines in the top window. This
number will be modified if the screen isn't big enough to handle
the full size.
-t title
Sets an xterm title bar to 'title'
-login Runs the programs under each window as though they were login
shells. This is useful to have csh source it's .login file,
bash source .profile, etc.
-nologin
Ovverrides any "set login on" statement in the startup file.
-rcfile file
Loads 'file' as the startup file instead of ~/.splitvtrc.
-norc Suppresses loading your ~/.splitvtrc
-f Allow setting the height of either the top or the bottom window
to less than 3 lines.
-v Print out the version number of splitvtDESCRIPTION
This program splits the screen into two windows, one above the other,
and runs a shell in each one. The default shell is taken from the
SHELL environment variable, or /bin/csh if SHELL isn't in the environ‐
ment, but another shell can be specified on the command line.
The top window is the default current window, but you can change to the
other by pressing ^W. Pressing ^V will quote the next character to the
current shell. Pressing ^O will put splitvt into command mode.
These special characters (command mode, switch window, and quote next
character) can be modified from within the .splitvtrc file.
When in command mode, splitvt will read one non-numeric character, per‐
form the requested command, and then revert to normal operations.
Numeric characters are interpreted as a parameter for the specified
command. The currently supported commands are:
'h' Print a help window for the escape commands
'-' Shrink the current window
'+' Expand the current window
'c' Select a block of text in the current window
'p' Paste the selected text to the current window
'k' Kill the current window (hangup signal)
'x' Lock the screen, after prompting for password
'r' Repaint the screen (clearing screen garbage)
'q' Quickly quit splitvt, killing the running shells
More functions may be added in the future.
If the -s command line option is used, the upper window will be bound
to the user defined number of lines even if the screen is resized.
Otherwise, the screen will be split into two equal parts based on the
new size of the screen.
The environment variable SPLITVT is set in the shells forked by
splitvt. In the shell running in the upper window, this variable is
set to the value "upper", while the shell running in the lower window
has this variable set to the value "lower". This is useful in shell
scripts to provide different behavior depending on which window the
script is running in. An example of this is shown in the file "menu"
in the examples directory in the splitvt distribution.
When splitvt starts up, it looks in your home directory for a file
named .splitvtrc You can set a number of parameters from within this
file, including all of the special characters, the default number of
lines in the upper window, whether or not to run the commands as login
shells, and even default commands to run in each window.
Here is an example of a .splitvtrc file:
# This is an example .splitvtrc file.
set command_char ^O
set quote_char ^V
set switch_char ^W
set upper_lines 12
run -upper /bin/sh
run -lower top
set login on
# This next line would override the above run statements
#run /bin/tcsh
If programs like vi are doing strange things to the window while in
splitvt, you probably need to set the LINES environment variable to a
correct value, or set the terminal's window sizing correctly. This
should be done automatically, but may need to be corrected.
If you are running under an xterm window, the title bar will probably
be updated to show the version of splitvt that you are running. Under
a true xterm window, you can also switch which half of the window you
are typing into by clicking the mouse in the half of the window in
which you want to type. You can also drag and drop the separator bar
by pressing down on the mouse button over the separator bar, holding it
down, moving the mouse to where you want the bar to end up, and then
releasing the button.
splitvt will attempt to erase the current utmp entry, and replace it
with entries for the two windows. This allows you to use programs such
as 'talk' within the splitvt windows. If you do not have write permis‐
sion to the /var/run/utmp file, you will not be able to modify the utmp
entries.
splitvt can be made set-uid root. splitvt will reset its user id to
that of the person running it, just before it exec()'s the shell under
the window. The splitvt process remains with root permissions, and
will change ownership of the pseudo terminals to that of the person
running splitvt, and then reset it to root when the window is closed.
SPLITVT IS NOT GUARANTEED TO BE A SAFE SET-UID PROGRAM!
I have done all I know to keep splitvt a safely usable set-uid program,
but I do not know everything, and am not responsible for any security
weaknesses splitvt might posess.
BUGS
When used with a certain public domain version of ksh, you have to man‐
ually kill -9 on the shell processes after you quit splitvt. This has
to do with a bug in that version of ksh (Version 06/03/86a and possibly
others).
If splitvt is compiled with xterm support, when run under an xterm, the
cut and paste feature is semi-disabled. The title bar may also be
reset to the string "xterm" after splitvt quits. See the comments at
the top of splitvt.c for how to disable xterm support.
Ansi colors are not repainted on screen refresh.
CAVEATS
There may be conflicts between splitvt's characters and other programs.
You can either change splitvt's default characters with command line
options, or you can type Ctrl-V (the quote character) within splitvt,
and the next character typed will be sent to the current window, no
matter what it is.
splitvt can only be used by terminals using vt100 emulation, due to the
use of specific vt100 escape codes. (vt300, xterm, Linux console, etc,
emulation also works)
When running in an xterm, if you press the escape key, you will have to
type another character in order for the escape to be seen by the run‐
ning program.
AUTHOR
Sam Lantinga slouken@cs.ucdavis.edu
SPLITVT 1/5/95 SPLITVT(1)
