{ datagubbe }

datagubbe.se » directory opus - king of the dual panes

Directory Opus - King of the Dual Panes

File management done right.

Autumn 2022

It's not exactly a secret that I'm a die hard Amiga zealot. I've previously sung the praise of AmigaOS itself, powerful applications like Amos Pro and Deluxe Paint and the programming tools supplied in a standard AmigaOS installation. This is just scratching the surface: the Amiga is blessed with a large library of excellent software. High quality programs like Lightwave 3D, PageStream, TV Paint, SAS/C and SCALA InfoChannel are some of its big name applications with a proven track record of professional use.

That's all good and well, but between all the major applications, there's the glue that keeps them together. Everyday workhorses just expected to be there and do their thing so that you can get on with your life. On the Amiga, one such program is Directory Opus. The biggest irony of AmigaOS is that even though it shipped with a complete desktop environment called Workbench, its mouse-driven file management always felt a bit clumsy. This is where Directory Opus comes in - but it's much more than just a small tool for shuffling files to and fro.

A standard DOpus screen showing the dual pane interface with several action buttons below the directory listers.

Paneful software.

At first glance, it might look like any old dual pane file manager, of which there are droves on pretty much all platforms. On DOS, Norton Commander was king of the hill, emulated by Midnight Commander in Linux and overtaken by Total Commander in Windows. There are hundreds, if not thousands, more: there was even one on the Xerox Alto. All of them are designed according to the same basic principle, but not a single one of them can compete with Directory Opus - or DOpus as it's affectionately called by its passionate user base.

Everything in DOpus can be configured, and I mean everything - the look and feel, the drop down menus, hotkeys, action buttons, screen layout, the mouse workflow behavior, the status bar contents, the lister format - and that's just the basics. What's even more impressive is that all of this configuration is an optional extra. The defaults are surprisingly sane and somehow fit right into the Amiga ecosystem. It feels like a natural extension of the OS and immediately eases into into your routine workflow, soon making you wonder however you managed without it. It's so indispensable that some users even boot straight into it, forgoing Workbench altogether.

Standard Behavior

Double click on an IFF image, a text file, a MOD tune or a sound sample, and DOpus will display or replay the file in question without the need for external programs.

The DOpus text reader with a find dialog open.

DOpus displaying a solution to Advent of Code 2021 day 6, written in ARexx.

Easily unpack or create LHA archives. Search for files by name or their contents. Bulk rename, copy, delete and move files. Check if a selected directory will fit on a floppy disk.

DOpus with a console window showing LHA output.

Unpacking an LHA archive.

Copying files on an old computer like an Amiga can be a tedious process, especially if floppy disks are involved. DOpus can be configured to display dual progress bars - one for the entire operation and one for the individual file currently being copied.

DOpus showing dual progress bars.

Alas, adding more bars won't make things progress any faster.

Mousing Around

The mouse workflow in particular is amazing. Drag an LHA archive from one panel to another to unpack it to the current directory of the target panel. Drag a directory from one panel to another and its contents will be displayed in the target panel.

Dragging an LHA archive in DOpus.

Drag to unpack!

If DOpus is running on the Workbench screen instead of on its own custom screen, any Workbench icon can be dropped into the DOpus window and DOpus will act according to its type. A device icon, for example, will open a file lister in the target panel.

Dragging the RAM disk icon into a DOpus lister.

On the Amiga, this behavior is called AppWindow and is considered very fancy.

Navigation feels equally instinctive. Left click the left- or rightmost panel border to quickly go to the parent directory. Right click the same border to go to the volume root. Click the panel header to select an arbitrary ancestor directory from a list.

Clicking a panel border to go up one level.

Clicking a panel border to go up one level.

Use the back and forward buttons surrounding the path entry field to go back and forth in history, just like in any modern web browser. When you revisit a directory during the same session, DOpus remembers what files you marked as selected the last time you visited.

Right click near the top or bottom of a panel and the file list will scroll up or down. The distance from the pointer to the panel border determines the scroll speed. Click-drag in a panel to multi-select, and the panel will automatically start scrolling when you come near the top or bottom of the file list.

The logic employed for selecting and deselecting files with the mouse, including when scrolling, just feels right; DOpus seems to know exactly where to stop inverting the selection when reversing a scroll-select, for example.

King of Config

What happens when a file is double clicked in DOpus? The short answer is that you decide. Should an internal viewer be employed to display the files contents or an external one? Should the file be executed? Opened in a text editor? Sent to a paint program?

Configuring the double-click action for a file.

Visage is a very fast image viewer for the Amiga.

You're the boss, and not only that - if DOpus shouldn't recognize a certain file type out of the box, you can create a new File Class to make sure it does. It even comes with a built in hex viewer.

Configuring a file class for PNG images.

The PNG format was invented after the release of DOpus, but that doesn't matter. Just move 1 byte, match the string "PNG" and Bob's your uncle! Note the many various operations that can be used to move around and examine the file.

In fact, the configuration options are so many and so detailed it's better just to show a few of them:

All buttons config.

The button bank configurator.

Button config.

The button configurator.

Buttons action config.

The button action configurator. Note the many various options for matching file selections.

List format config.

The file list configurator.

Many advanced config options.

The many detailed options should give an idea of the immense level of control DOpus affords the power user.

The Missing Link

Like many fellow Amiga users, I'm exceptionally fond of Directory Opus. I've tried finding a similar replacement on many other platforms, to no avail. There's a modern Windows version of the program, still developed by Jonathan Potter - the original author - but the workflow and UI differs too much from that on the Amiga. There's a lookalike on Linux called Worker, which at first glance seems very promising. It sadly falls short on almost every detail that counts, such as the mouse workflow and extensive configurability. They're not bad programs - they're just not the same.

Part of the excellent DOpus experience is no doubt my own habits, formed during my early years of computer use. Part of it is its seamless integration into the Amiga way of doing things. But the major part of it is DOpus itself - a program so good at what it does it's hard to recreate and almost impossible to improve upon.

I'm very happy to have gotten to know such a piece of software.