VIOS comes with four development tools in the spirit of a Smalltalk environment, built on the display server described in The GUI:

The ESP does all the navigation, scrolling and editing inside the tool windows. The CPU only fills the panes and acts on what you choose. The tools' engine (kernel/vios_tools.c) runs from the REPL's idle hook: it acts when the console is waiting for input, exactly as if you had typed the command there. While a program runs in the foreground, the tool windows still scroll and edit, but your choices (an accept, a refresh) are carried out only when the program returns to the prompt.

Opening the tools

• Keyboard. Ctrl+Shift+B, Ctrl+Shift+W, Ctrl+Shift+I and Ctrl+Shift+M open the Browser, Workspace, Inspector and Manager from anywhere. A tool that is already open is brought to the front instead.
• World menu. In the Smalltalk style, F10 opens the World menu with the four tools. In the Turbo Vision style the same four commands are the entries of the menu bar along the top: F10 runs the first (Browser), Alt+B, Alt+W, Alt+I, Alt+M run the others.
• Command palette. Ctrl+K (or Ctrl+Shift+P) and type part of the name.
• From Forth. TOOL ( n -- ) opens or focuses tool n: 0 Browser, 1 Workspace, 2 Inspector, 3 Manager. -1 TOOL closes all of them.

0 TOOL                                   \ the Browser
-1 TOOL                                  \ close every tool window

Close a tool with Ctrl+W (or Alt+F3) while it has the focus. Inside every tool, Tab and Shift+Tab move between panes, Ctrl+Tab and Ctrl+Shift+Tab change tabs, Ctrl+R refreshes the contents and Shift+F10 opens the tool's own menu (the pane menu). Keys that a tool window does not use are dropped rather than passed to the console.

The tools' accelerators are global: Ctrl+Shift+B/W/I/M and Ctrl+R are taken by the window manager in every window, including your own.

The Browser

The Browser has three list panes along the top, a code pane below them and a status line at the bottom.

• Modules pane (left): (all) (every word in the dictionary), (core) (words that belong to no module), then each module, marked with * when it is active. Moving the selection updates the other panes at once.
• Words pane (middle): the words of the selected module. Typing a letter jumps to the next word starting with it.
• Info pane (right). For a module: version, crc (of the source), the number of words and token bytes, one needs NAME ok or needs NAME stale line per dependency (stale when the dependency's source changed since), and a used by NAME line for every module that depends on this one. For a word: its kind (primitive, colon, constant, variable, defer, native) and xt, its token and direct code sizes, its module and, for constants and variables, its value.
• Code pane: the exact source of the selected module, or the retained source of the selected word. It is an ordinary editable text view.
• Status line: what the selection is and what you can do, for example DEMO: active Ctrl+S accept Shift+F10 menu.

Accept (Ctrl+S in the code pane). What happens depends on what is shown:

• A module. The code pane's text becomes the module's new source: it is streamed into the workbench draft, compiled and tested in isolation (stage), then activated, the same revision-checked steps as F5 and F6 in the text workbench. On success the status line says DEMO active; words 52% code 31% map 20%, showing how full the dictionary, the code space and the source map are. Every accept keeps the replaced version's code until the next restart, so when any of them passes 80 % the line names the fullest one instead, for example DEMO active; code 84%: save, restart. On failure it says not accepted: and the reason, and the live module is not touched. After an accept the words and info panes show the new version at once; the code pane keeps your text.

- A single word. The text (at most 255 bytes) is evaluated, so the word is redefined, the way a Smalltalk method accept works. For a word that belongs to a module the status line warns that this redefines it outside its module: the module's source is unchanged.

Pane menu (Shift+F10):

The panes are separated by one-pixel divider lines, vertical between the lists and horizontal above the code pane.

The Workspace

The Workspace is a text view for trying things out. It opens with a reminder:

\ Ctrl+D do it, Ctrl+P print it, Ctrl+I inspect it
3 4 + .

Select some text (Shift with the arrow keys, or Ctrl+A for everything) and press a key; with nothing selected the key works on the caret's line, which it selects first. The selection may be up to 255 bytes. Evaluation uses the same data stack as the console.

On an error the message is inserted after the selection, selected, so one Backspace removes it: NO-SUCH-WORD error: unknown word: NO-SUCH-WORD.

The Inspector

The Inspector has five tabs over a table and a read-only detail pane. Change tabs with Ctrl+Tab, or Left/Right while the tabs have the focus. The contents are a snapshot: press Ctrl+R to refresh.

Memory paging. The memory table never ends: moving Up from the first row shows 8 bytes earlier, Down from the last row 8 bytes later, PgUp and PgDn at the edges move by 64 bytes. To jump somewhere, put the address on the stack (for example in the Workspace) and choose Go to address from the pane menu.

Pane menu (Shift+F10): Refresh, Go to address (the top of the data stack becomes the memory view's start), Kill task (on the Tasks tab: asks for confirmation, then TASK-KILLs the selected task; Enter on a task does the same).

The Manager

The Manager has two tabs.

• Boot: three actions, Trial the candidate slot, Confirm the running slot and Revert to the confirmed slot, with the boot status and manifest in the detail pane (see Modules and Persistence). Enter on an action asks for confirmation first.
• Modules: every module with its version and whether it is active. Enter asks to save the selected module to SD; Rollback in the pane menu asks to roll back its latest activation.

The result (done, or failed: and the reason) appears in the detail pane.

The confirmation is a modal Confirm dialog (window 24) with Yes and No buttons. It dims the rest of the screen and keeps the focus until you answer. No has the focus, so Enter on its own cancels; Tab (or Shift+Tab) moves to Yes, then Enter or Space confirms. Esc also cancels.

Pane menu (Shift+F10): Refresh, Save to SD, Rollback.

Keyboard reference

Keys are resolved on the ESP in this order: an open menu or palette, the keyboard pointer, move/resize mode, the menu keys, the command palette, command accelerators, window keys, the focused widget, and finally (if nothing used the key and the window allows it) the CPU's keyboard input.

Display and windows

Menus and commands

Move/resize mode (Ctrl+F5) and keyboard pointer (Ctrl+F12)

Widgets

Text views (Browser code pane, Workspace, detail panes)

Tools

Text workbench

The text workbench

Before the windowed tools, VIOS had a text workbench: a full-screen module browser, inspector and source editor on the 80 x 60 text screen. It is still there, and it is also what the Browser's accept uses underneath. Under the GUI it opens as a full-screen window (window 26) above the desktop and owns the keyboard while open, so F5, F6 and F10 mean stage, activate and close there, not zoom, next window and menu.

Open it with WB-OPEN at the console or with F1 from the console; F10 closes it and F1 goes back to the console, keeping the draft. The screen has the browser on the left (modules, or the words of one module), the inspector at the top right (the selected word or module, the data stack and BASE, dictionary use) and the source editor below it, with the draft's state (MODIFIED/CLEAN, STAGED, ACTIVE, SAVED, size and revision) and the last error along the bottom. There is one draft of up to 4096 bytes and one undo step. Kernel words are read-only; choosing a module word edits its module.

The WB- names are console commands, not dictionary words: type each on a line of its own, with its arguments after it; they cannot be compiled into a definition. Most print a WB-STATUS line describing the draft. Every editing command takes the draft's current revision and refuses a stale one, so two clients (the keyboard and the host harness, say) cannot overwrite each other. This session creates, tests, activates and saves a module:

WB-NEW HELLO 1 0

The status line now says revision 2. Insert : SEVEN 7 ; and a line feed (given in hex) at offset 0, which makes it revision 3, and read it back:

WB-PATCH 2 0 0 3A20534556454E2037203B0A
WB-SOURCE 0 12

Stage (compile and test in isolation), activate, and use it:

WB-STAGE 3
WB-ACTIVATE 3
SEVEN .

Save the active module to the SD card:

WB-SAVE 3

The screen is painted by the deferred word WB-PAINT, which runs at the idle boundary with a temporary stack and a budget of 4096 instructions. If you replace it and your painter fails, painting stops but the draft is safe; put the default back with:

' WB-PAINT-DEFAULT IS WB-PAINT

(followed by WB-REDRAW on the board).

Console and editor

The REPL is the Console window on the desktop (74 x 28 cells, scrolling through 58 lines). Its last row reminds you of the keys: VIOS console F1: editor Up/Down: history. F1 switches between the console and the text workbench, Ctrl+Alt+F1 between the desktop and a full-screen text console with the same contents. See The Console and REPL for line editing and history.