January 7, 2001 RVT 1

NAME

rvt - a specialized VT100 emulator for the X window system

SYNOPSIS

rvt [-v] [-l username] [-display display-name] [-geometry window-geometry] [-bg color] [-fg color] [-bd color] [-bw number] [-font fontname] [-fb fontname] [-name name] [-sl number] [-cc char-class] [-sb] [-rw] [-rv] [-msg] [-iconic] remote-machine

DESCRIPTION

The rvt program is a VT100 terminal emulator for X. It is intended as a partial replacement for xterm(1) for users who do not require the more esoteric features of xterm(1). Specifically rvt does not implement the Tektronix 4014 emulation, session logging and toolkit style configurability. As a result, rvt uses much less swap space than xterm(1), a significant advantage on a machine serving many X sessions.

The rvt program is based on the xvt(1) terminal emulator. However, it has been modified specificly for use with the dvt(1) program. It may be used as a stand-alone application, but it is not suggested that the user do so. The following options are available:

-v: Prints the version of ClusterIt to the stdout, and exits.
-l username: If the program specified by the RLOGIN_CMD environment variable allows the user to pass a username with a -l option or ssh(1) (Such as some versions of rsh(1)) then the rvt program will pass the appropriate flags to the remote-connection command to attempt to connect to the remote machine as the username specified.
-display display-name: Attempt to open the rvt window on the named X display. In the absence of this option, the display specified by the DISPLAY environment variable will be used.
-geometry window-geometry: Create the window with the specified X window geometry.
-background color: Use the specified color as the window's background color.
-bg color: This option is a synonym for -background
-foreground color: Use the specified color as the window's foreground color.
-fg color: This option is a synonym for -foreground
-bd color: Set the border color. As with border width, this option will usually be disregarded with respect to the window's outer border. It does, however, set the color of the line separating the scroll bar from the main part of the window.
-bw number: Set the window border width to number pixels. Many window managers ignore existing window borders and contruct their own. If you are using such a window manager, this option will be ignored.
-font fontname: Set the main text font to be used by rvt
-fb fontname: Set the font used for the vt100 bold rendition style. Unlike xterm(1), the current version of rvt will not try and create bold text by displacing and or'ing an ordinary font. Therefore if you want bold highlighting to work, you need to use this option to specify a suitable bold font.
-name name: Set the name that is used when looking up X resource values for this instance of .
-sl number: Set an upper bound for the number of lines of text that will be saved when they have scrolled off the top of the window.
-cc char-class: Input or modify the character classes that are used to determine what is a word when a double-click is used to select a word of displayed text. This is identical to the same option in xterm(1). See the xterm(1) manual page for a description of the syntax of string.
-sb: Start up with the scrollbar visible. The scrollbar can be displayed or hidden at any time, simply by holding down the CONTROL key on the keyboard and pressing any mouse button. The visibility of the scrollbar does not determine whether scrolled text is saved or not, as with xterm(1), text scrolled off the top of the window is always saved up to the current maximum number of lines.
-rw: Enable reverse wrapping of the cursor, so that lines typed to a shell that are longer than the width of the screen can be edited. This is the same as the xterm(1) reverse wrap option.
-msg: Enable messages to the terminal window from programs like write(1). By default, rvt windows have messages disabled. Executing an rvt window with the -msg option has the same effect as running it normally, and executing the command `mesg y' to enable messages.
-rv: Run in reverse video - that is, exchange the foreground and background colors. This option has no effect if either the foreground or background are set explicitly.
-iconic: Start up with the window already iconized. remote-machine The name of a remote machine to connect to. The connection attempt is made via the program specified by the RLOGIN_CMD environment variable.

X RESOURCES

Most of the command line options have X resource counterparts and these are listed in the following table. Like xterm(1), rvt uses the class name XTerm, so resource options set for XTerm will work for both xterm(1) and rvt windows.

Command line options and X resources

X resource
Commandline Instance Class
`-`l	-	-
`-`display	-	-
`-`geometry	geometry	Geometry
`-`bg	background	Background
`-`fg	foreground	Foreground
`-`bd	borderColor	BorderColor
`-`bw	borderWidth	BorderWidth
`-`font	font	Font
`-`fb	boldFont	BoldFont
`-`sl	saveLines	SaveLines
`-`sb	scrollBar	ScrollBar
`-`rw	reverseWrap	ReverseWrap
`-`cc	charClass	CharClass
`-`msg	messages	Messages
`-`iconic	iconic	Iconic

THE SCROLL BAR

Lines of text that scroll off the top of the rvt window are saved automatically (up to a preset maximum number) and can be viewed by scrolling them back into the window with the scrollbar. The scrollbar itself can be displayed or hidden by clicking any mouse button in the window while holding down the CONTROL key on the keyboard. When using the scrollbar, the left and right mouse buttons are used for scrolling by a few lines at a time and the middle button is used for continuous scrolling. To use the middle button, press it in the scroll bar and hold it down. The central shaded part of the scrollbar will then attach itself to the cursor and can be slid up or down to show different parts of the sequence of saved lines. When scrolling with the left and right buttons, the left button is used to scroll up and the right is used to scroll down. Assuming that there are enough hidden lines, the distance scrolled with either button is equal to the number of lines between the cursor and the top of the window. Hence, pressing the left cursor opposite a line of text will result in that line being moved to be the top of the window and pressing the right button will cause the top line to be moved down so that it is opposite the cursor.

TEXT SELECTION AND INSERTION

Rvt uses the same kind of text selection and insertion mechanism as xterm(1). Pressing and releasing the middle mouse button in an rvt window causes the current text selection to be inserted as if it had been typed on the keyboard. For the insertion to take place, both the button press and the button release need to be done with the cursor in the rvt window.

The left and right mouse buttons are used to select text, with the left button being used to start a selection and the right button being used to modify an existing selection. Any continuous block of displayed text can be selected. If both ends of the text block are visible in the window then the easiest way to select it is to position the cursor at one end and press the left mouse button, then drag the cursor to the other end with the button held down before releasing the button. If the block is larger than the window then you must first use the left mouse button to select one end, then use the scroll bar to scroll the other end into view and finally use the right mouse button to extend the selection. The effect of pressing the right mouse button is to move the nearest end of the current selection to the current cursor position.

The other way to make selections in rvt is to use double and triple clicks of the left mouse button with a double click selecting a word and a triple click selecting a whole line. For this purpose, a word is a sequence of characters in the same class. The default character classes are:

The upper and lower case letters, digits and `_' (underscore) all in one class;
The white space characters all in one class;
Each of the remaining punctuation characters in a class by itself.

If you want to change the character classes so that, for example, you can select a UNIX pathname or a mail address in one double click, then you can do so by using the -cc command line option or the charClass X resource. Multiple clicking can be combined with dragging to select a sequence of consecutive words or lines.

Although rvt essentially mimics the behaviour of xterm(1) in its support of text selection and insertion, there are a couple of minor differences:

rvt respects TAB characters in selected text and does not automatically convert them into spaces as does xterm(1);
rvt will let you abort a text insertion if you realize you have made a mistake before releasing the middle mouse button.

ENVIRONMENT

rvt utilizes the following environment variables.

DISPLAY: The default X server that the client should connect to.
RLOGIN_CMD: The default command that will be run to connect to the remote host. This can be anything from rsh(1), ssh(1), to telnet(1) because rvt is an interactive process, automatic authentication is not required as it is with dsh(1).

DIAGNOSTICS

Exit status is 0 on success, 1 if an error occurs.

HISTORY

The rvt command appeared in clusterit 2.0.

AUTHOR

Rvt is based on the program xvt(1) written by John Bovey, University of Kent, in 1992. Modifications to make this program compile on modern machines, and work with dvt(1) were made by Tim Rightnour.

BUGS

Pasting very large quantities of text does not work.