tHermes, the interactive Hermes

tHermes is the version of Hermes which communicates with the user through standard character display terminals, including X11 terminal windows. It organises the terminal screen in a special window-like way. It is however not a graphical user interface (GUI).

Permanent windows

The most important permanent components (windows) of the screen lay-out are:

Common Output Area (COA), the top part of the screen which shows a part of the log file. Here user commands are logged and tasks can write text.
Task Status Area (TSA). This normally consists of four lines above the User Command Area which each can contain information reflecting the current status of a task.
User Command Area (UCA). This occupies the lower two lines of the terminal screen and is the focus of user-to-task communication.

Other permanent components are a clock display and numbers which indicate which part of the log file is mapped to the COA.

Transient windows

Components of the screen lay-out which are not permanent are called transient windows. These overlay the permanent screen components or other transient windows. For example the context-sensitive help display overlays (part of) the COA. Other examples of transient windows are a menu window allowing the user to change specific task settings, prompter windows in which for instance a search string can be specified, a Unix shell window, etc.

Control keys and escape sequences

Many functions of tHermes can be invoked by typing a control key (designated as CTRL-c, where c is a letter), or by typing an escape sequence (the ESC character followed by another character).

Important control keys are:

CTRL-O: switch `keyboard focus' between terminal windows waiting for keyboard input,
CTRL-C: abort a task or break out of a transient window (depending on keyboard focus)
CTRL-L: redraw the whole terminal screen
CTRL-Q: terminate Hermes. Hermes can also be terminated by typing `CTRL-X CTRL-C' or `ESC Z' or by typing QUIT, STOP, END or EXIT in the UCA.

Only one GIPSY session in a directory

It is not possible to run more than one GIPSY session in the same directory. If tHermes is started in a directory where GIPSY already runs, it exits immediately with an error message. (But nHermes will wait until the other session is finished.)

The reason for this restriction is that most data structures used by Hermes (e.g. the keyword file, the log files etc.) cannot be shared. Is is however possible to access GIPSY sets in the same directory from multiple sessions started in different directories. This can be done by changing Hermes' working directory.