Comments on My Brain Hurts: Building Mono for Android

As a final note to my previous post, my .Net app r...

2009-04-01T08:23:00.000-07:00

As a final note to my previous post, my .Net app runs as expected on Linux Ubunty Hardy but was developed in #D on Windows.

I have not tried with an app developed in MonoDevelop on Linux.

I followed your instructions trying to run in the ...

2009-03-31T21:05:00.000-07:00

I followed your instructions trying to run in the Android emulator a .Net 2.0 Winforms application (graphics, audio) created in SharpDevelop on Vista. First I tried using Mono.apk; my app crashed, the error raised was something like "Winforms assembly not found". Then I mounted your sdncard.img image file (the one with debian and mono prebuilt), launched the Android emulator with the mofified ext2 kernel image, then tried to run /sdcard/kit/bash.sh. As you know, files on the sdcard cannot be either run or set as executables. So I opend bash,sh on my Linux box and then executed the commands within in the Android shell. Finally, I copied my .net executable and files from my Linux box to the /home folder in the debian mounted system. Upon issuing mono myapp.net it crashed with an error message pointing to a unimplemented property in Winforms.

Bottom line, mono for debian-arm is not yet up to the job.

Congratulations on making it possible to get this far!

Hi there,Is it likely that consumers could benefit...

2009-01-13T09:39:00.000-08:00

Hi there,

Is it likely that consumers could benefit of these developments ? I mean could I develop applications for the Android platform that users could run on a G1 for example without having to do anything else then installing my app ?

Hi Richard, I've fixed the assertions/exceptions. ...

2009-01-10T17:18:00.000-08:00

Hi Richard, I've fixed the assertions/exceptions. See http://www.koushikdutta.com/2009/01/mono-for-android-first-update.html for more information as well as an updated APK.

Sure, give me a moment. I've successfully gotten m...

2009-01-08T21:25:00.000-08:00

Sure, give me a moment. I've successfully gotten mono compiling and working with eglib. That decreases the footprint of Mono considerably.

I'm working on linking it with bionic now (Android's libc). After that is done, it should run on Android's flavor of Linux flawlessly.

I tried recompiling but I still get the error. Thi...

2009-01-08T21:22:00.000-08:00

I tried recompiling but I still get the error. Think you could upload your working /usr/local/bin/mono to rapidshare for me?

Hmm possibly, but I don't see why it would. Try us...

2009-01-08T16:58:00.000-08:00

Hmm possibly, but I don't see why it would.

Try using the vanilla /sdcard/kit/bash.sh that I provided and verify that it works.

Feel free to email me at koushikdutta at hotmail dawt cawm

Yes, after running a chroot. I wonder if this prob...

2009-01-08T16:54:00.000-08:00

Yes, after running a chroot. I wonder if this problem is because I mounted it under /sdcard/kit/mnt instead of under /data. What do you think?

Richard, is that happening under Debian?

2009-01-08T16:45:00.000-08:00

Richard, is that happening under Debian?

Using your sdcard.zip I get a:Unhandled Exception:...

2009-01-08T16:21:00.000-08:00

Using your sdcard.zip I get a:

Unhandled Exception: System.TypeInitializationException: An exception was
thrown by the type initializer for Mono.CSharp.Location --->
System.ExecutionEngineException: SIGILL
at System.Collections.Hashtable..ctor (Int32 capacity, Single loadFactor, IHashCodeProvider hcp, Icomparer) [0x00000]
at System.Collections.Hashtable..ctor (Int32 capacity, Single loadFactor) [0x00000]
at System.Collections.Hashtable..ctor () [0x00000]
at Mono.CSharp.Location..cctor () [0x00000] --- End of inner exception stack trace ---

whenever I run gmcs or gmcs hello.cs without an exe being created. Strangely, mono hello.exe prints out the "Hello World!" message and then the error above. Any ideas?

Hopefully I'll have a simple Mono APK available on...

2009-01-07T14:50:00.000-08:00

Hopefully I'll have a simple Mono APK available on the Market later this week!

Total disk footprint of Mono and all it's dependen...

2009-01-07T14:49:00.000-08:00

Total disk footprint of Mono and all it's dependencies is 6598288. I'm trying a build with eglib now (and I'm also going to change the path of the linker and see if it works on Android out-of-box). Crossing my fingers...

Rapidshare is a good upload site. I too can't acce...

2009-01-07T11:36:00.000-08:00

Rapidshare is a good upload site. I too can't access the sdcard.zip and this measly laptop would take hours for me to compile myself. Thanks for all your hard work.

To elaborate further on why "--dynamic-linker ld-l...

2009-01-07T11:24:00.000-08:00

To elaborate further on why "--dynamic-linker ld-linux.so.3" works (in case it isn't obvious).

Since it is not a full coded path, executables will look for that file in their (current) directory at runtime.

I should probably write this up in a separate post-- I know a lot of other Android developers are also trying to make the standard ARM/Linux build outputs work on Android.

The downside to this is that libc.so.6 is 5 times the size of /system/bin/libc.so. And we'd effectively be loading the same library twice into memory. The optimal solution is to recompile everything to reference Android's libc.so. Or, maybe customize ld-linux.so.3 to special case libc. But that might not work-- I'll take a wild stab and say that Android's libc may just be a subset of ARM/Linux libc due to the disparity in file sizes.

I've tried the -static flag; it doesn't work; didn...

2009-01-07T11:15:00.000-08:00

I've tried the -static flag; it doesn't work; didn't look into it further though. It's a bit of a kludge. :)

The cause of the problem is that mono is looking for the linker at /lib/ld-linux.so.3, which does not exist on Android. Android's linker is /system/bin/linker. However, by using the --dynamic-linker option on ld, you can change where an executable looks for the linker.

So, basically by passing "--dynamic-linker ld-linux.so.3" to the linker during make, and make sure that the linker (and all of Mono's dependencies) are in the same directory as mono.

I've tested with a few simple programs to verify it works-- and it does.

Furthermore, this should work for *all* phones, not just jailbroken ones.

Here are the list of dependencies of Mono (each dependency may have further unlisted dependencies).

libgthread-2.0.so.0
libglib-2.0.so.0
librt.so.1
libdl.so.2
libpthread.so.0
libm.so.6
libgcc_s.so.1
libc.so.6
libpcre.so.3
/lib/ld-linux.so.3

I can see that m(iguel?) is intensely interested i...

2009-01-07T11:14:00.000-08:00

I can see that m(iguel?) is intensely interested in getting Mono to run on Android. I can't blame him, as I too would love to see Mono run on ... everything!

I'll be watching this blog closely. I don't have a G1 to test with yet, the Agora Pro is on the top of my list though.

What are the dyanamic dependencies that you have?W...

2009-01-07T11:05:00.000-08:00

What are the dyanamic dependencies that you have?

Would you mind running: ldd mono?

You could try passing the "-static" flag to the GCC command line that produces the `mono' executable.

I'll look into getting a mirror.

2009-01-06T19:52:00.000-08:00

I'll look into getting a mirror.

Think you could upload your sdcard.zip file elsewh...

2009-01-06T19:50:00.000-08:00

Think you could upload your sdcard.zip file elsewhere? My download speed slows to a crawl after a couple minutes of downloading. Thanks.

Thanks for posting the instructions!

2009-01-06T10:13:00.000-08:00

Thanks for posting the instructions!