Midnight Fane 3 Dart. Name Special Location. On Hit of Shaken or Frightened: Fort(DC22) Prone for 1rnd and 1d12 Neg dmg Midnight Fane 3 Touch of Mercy +4, Bleed. (Commander). From a Dead. The Midnight Commander package from the above example is available for download. DMG images can be attached and deattached from inside darling shell with hdiutil.
Linux users who want to run Windows applications without switching operating systems have been able to do so for years with Wine, software that lets apps designed for Windows run on Unix-like systems.
There has been no robust equivalent allowing Mac applications to run on Linux, perhaps no surprise given that Windows is far and away the world's most widely used desktop operating system. A developer from Prague named Luboš Doležel is trying to change that with 'Darling,' an emulation layer for OS X.
'The aim is to achieve binary compatible support for Darwin/OS X applications on Linux, plus provide useful tools that will aid especially in application installation,' Doležel's project page states. Darwin is Apple's open source operating system, which provides some of the backend technology in OS X and iOS. The name 'Darling' combines Darwin and Linux. Darling works by 'pars[ing] executable files for the Darwin kernel... load[ing] them into the memory... and execut[ing] them.'
But there is a ways to go. 'Darling needs to provide an ABI-compatible [application binary interface] set of libraries and frameworks as available on OS X... by either directly mapping functions to those available on Linux, wrapping native functions to bridge the ABI incompatibility, or providing a re-implementation on top of other native APIs,' the project page notes.
Doležel, who started Darling a year ago, described the project and its progress in an e-mail interview with Ars. Darling is in the early stages, able to run numerous console applications but not much else. 'These are indeed the easiest ones to get working, albeit 'easy' is not the right word to describe the amount of work required to achieve that,' Doležel said. 'Such applications include: Midnight Commander, Bash, VIM, or Apple's GCC [GNU Compiler Collection]. I know it doesn't sound all that great, but it proves that Darling provides a solid base for further work.'
AdvertisementUsers must compile Darling from the source code and then 'use the 'dyld' command to run an OS X executable,' Doležel said. One roadblock is actually getting Mac .dmg and .pkg application files working on a Linux system. Because doing so isn't that straightforward, Doležel said, 'I've written a FUSE module that enables users to mount .dmg files under Linux directly and without root privileges. An installer for .pkg files is underway.'
Unix/Linux synergy
The fact that OS X is a Unix operating system provides advantages in the development process. 'This saved me a lot of work,' Doležel explained. 'Instead of implementing all the 'system' APIs, it was sufficient to create simple wrappers around the ones available on Linux. I had to check every function for ABI compatibility and then test whether my wrapper works, so it wasn't as easy as it may sound.'
Another lucky break not available to Wine developers is that Apple releases some of the low-level components of OS X as open source code, 'which helped a lot with the dynamic loader and Objective-C runtime support code,' Doležel noted.
But of course, the project is an extremely difficult one. Doležel isn't the first to try it, as Darling was initially based on a separate project called 'maloader.' Doležel said he heard from another group of people 'who started a similar project before but abandoned the idea due to lack of time.'
Doležel was actually a novice to OS X development when he started Darling, being more familiar with OS X from a user's perspective than a developer's perspective. 'I have personally looked for something like Darling before, before I realized I would have to start working on it myself,' he said.
Darling relies heavily on GNUstep, an open source implementation of Apple's Cocoa API. GNUstep provides several core frameworks to Darling, and 'the answer to 'can it run this GUI app?' heavily depends on GNUstep,' Doležel said. Doležel is the only developer of Darling, using up all his spare time on the project.
AdvertisementNo reverse-engineering
Doležel isn't reverse-engineering Apple code, noting that it could be problematic in terms of licensing and also that 'disassembling Apple's frameworks wouldn't be helpful at all because Darling and the environment it's running in is layered differently than OS X.'
The development process is a painstaking one, done one application at a time. Doležel explains:
To improve Darling, I first take or write an application I'd like to have running. If it is someone else's application, I first examine it with one of the tools that come with Darling to see what frameworks and APIs it requires. I look up the APIs that are missing in Apple's documentation; then I create stub functions for them and possibly for the rest of the framework, too. (Stub functions only print a warning when they are called but don't do any real work.)
The next step is to implement all the APIs according to the documentation and then see how the application reacts. I also add trace statements into important functions to have an insight into what's happening. I believe this is very much like what Wine developers do.
When things go wrong, I have to use GDB [GNU Debugger] to debug the original application.
It is rather unfortunate that Apple's documentation is often so poorly written; sometimes I have to experiment to figure out what the function really does. Many OS X applications seem to contain complete pieces of example code from Apple's documentation, presumably because one would have to spend a lot of time getting to understand how the APIs interact. This is why I appreciate open source so much—when the documentation is sketchy, you can always look into the code.
Years of development are needed. Similar to Wine, 'Having a list of applications known to be working is probably the best way to go,' Doležel said.
Darling should work on all Linux distributions, he said, with the catch that 'many apps for OS X are 32-bit only, and installing 32-bit packages on a 64-bit Linux system could be tricky depending on your distribution. I personally use Gentoo Linux, so I'm gradually creating a Portage overlay that would compile Darling and all dependencies for both 32-bit and 64-bit applications.'
Doležel would like to bring Angry Birds, other games, and multimedia applications to Linux. Darling could potentially 'be used to run applications compiled for iOS,' he writes on the project site. This will also be a challenge. 'The intention is to support the ARM platform on the lowest levels (the dynamic loader and the Objective-C runtime),' he writes. 'Rewriting the frameworks used on iOS is a whole different story, though.'
Recently, I had a friend, a serious Linux aficionado, come over and we had occasion to sit in front of my machine while I was doing some console work. I do a lot of work under OS X using the GUI, and previously that is what had been on-screen when he had visited. This time, however, I had some consoles open to one of my web servers.
I did a few things during which he was uncharacteristically silent. During a pause in my typing, he spoke up with a note of real interest: “That’s unbelievably awesome. What is that?”
“Midnight Commander”, I told him.
Now he uses Midnight commander too. All the time. I thought I’d tell you why.
Midnight Commander is a program that allows you to work at many times the rate you would if you were simply typing console commands. While you are far better informed than you would otherwise be.
It’s a file manager for the console (if you’re familiar with Norton Commander, that’s exactly the type of application this is), but to call it “a file manager” is to understate the case dramatically. You need to understand up front that Midnight Commander is a very mature application. It is simply chock-full of useful capabilities. It doesn’t 100% replace the console, but it comes very close.
You can have multiple panes showing you different directories. You can copy and move between these directories with great ease without ever typing a file name. These directories can be on different machines using either FTP or SSL connections. You can change permissions, run arbitrary console commands at any time, even on files in the various directory panes. You can sort, view, change and otherwise variously mess with things in oodles of useful ways many times faster than you can from the command line. You can directly see and navigate inside .tar archives, zips and more. There’s a built-in screen editor you can enable that is syntax-aware and just generally a pleasure to use, or you can continue to use whatever console-based editor you prefer (but you really should learn to use Midnight Commander’s editor. Trust me.)
Midnight Commander Dmg 5e
There’s still more — a whole lot more — but suffice to say that once you wrap your head around Midnight Commander, you’ll be a convert to it forever.
For Linux, typically you update your distribution and then use apt-get or whatever package manager you prefer to install mc — I did it this way:
How To Use Midnight Commander
For OS X, it’s a little tougher to find an easy installation, particularly for the latest versions of Midnight Commander, but there are .dmg files out there that will do it for you. It is entirely worth the effort; I encourage you to get after it right away.
Midnight Commander Mc
Installing from source code is tough; Midnight Commander’s compilation process is riddled with dependencies. Under OS X as supplied from Apple, these are quite difficult to resolve without adding a lot of other things as well. Still, it can be done; I’ve done it.
Some of the generalized make-OSX-support-Linux packages such as fink and MacPorts can make this a lot easier, but beware: I’ve tried both of these, and they arbitrarily change some of the system software, such as the installed Python and Perl versions.
If that’s okay with you, then by all means, go that route. If new versions of things like Python and Perl are going to break your code, I’d advise you to go about this very carefully. Perl in particular has a tendency to go from working scripts to non-working scripts when you change installed versions.