Using X-Terminals in the CSB Core

There are a number of X-terminals in the Core User Area and associated labs. These are configured to present a login screen, showing the name of the X-terminal, and the name of the host computer controlling the login session.

To log in, simply enter your username and password as you would at any of the workstation screens. You will be presented with an environment similar to the one you get on a workstation.

In this document, you can read about When to use an X-Terminal, Keyboard Mapping, Logging onto Different Hosts, Advanced Features, and Running Netscape on an X-Terminal.

When to use an X-Terminal

X-terminals are perfectly adequate for many applications, including editing and running non-graphics programs. Color X-terminals can run many graphics programs, mail, and netsurfing (but see below). X-terminals should be adequate for running programs like the HKL package (Denzo/Xdisp).

When Not to use an X-Terminal

Our color X-terminals have limitations.

• They do not support GL or OpenGL applications. This means that a number of SGI graphics utilities will not display on them. EG, the jot editor won't work (although nedit will). It also means that a number of molecular graphics programs won't work at all.
• They have only 8 bit-planes (which limitation they share with some of the workstations). This means that they are limited to 256 different colors. Graphics programs which draw finely shaded pictures will produce inferior results. Some groups of applications will be unable to coexist, because their cumulative demand for color slots exceeds 256.
• Their resolution is 1024x768, which is smaller than the 1280x1024 on most of the workstations.

Keyboard Mapping

When used in the default manner, the X-terminal keyboards will be configured to be similar to the SGI keyboard. IN particular, the rubout key is mapped to BackSpace instead of Delete. The group of six keys above the arrow keys (to the right of Return) have also been remapped to take on the SGI functions. The new (SGI-style) functions are amrked on the keys in red.

Logging onto Different Hosts

The X-terminals are configured so that you will log on to a specific host, csbmet at this writing. The usual way to log onto a different host is to first log onto the default, then telnet or rsh to the desired host.

Accessing Advanced X-Terminal Features

There are a numbner of features and local clients supported by the X-terminals. These include a local window manager, multiple terminal windows (including LAT protocol), and X-terminal management functions. These can be accessed, with some difficulty, through the X-terminal console (left-Alt-F3).

Running Netscape

Netscape will happily allocate and use all available colors on an 8-bitplane display like the X-terminals (and some of the workstations). Once Netscape is running, other applications may fail to start, giving an error of the form, unable to allocate colormap entries. You can avoid this by using the qualified command, netscape -install. A private colormap will be allocated to netscape, which won't interfere with other applications. However, you will get interesting effects as you move the cursor in and out of the netscape window.

Revised: Thursday, 04-Dec-1997 14:46:02 EST
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