This article has 78 Comments

1. Great. Thanks for the instructions.
   Any idea how start your C program when the system boots up, or after it boots up?

2. Hi
   when i run the following on my Ubuntu 9.04:
   $ sudo apt-get install lib32readline5-dev
   I am getting the following error:
   E: Couldn’t find package lib32readline5-dev
   how did u resolve this?

3. That’s only for ubuntu intrepid users.

   You won’t need it in 9.04 desktop.

   I’ve modified the post to reflect this as well.

4. Hi,

   Thanks for the instructions.
   Just a little modification, you need to change agcc, as the toolchain is not correct libgcc.a is not anymore in interwork folder, so 2 lines needs to be changed too.

   “$TOOLCHAIN/lib/gcc/arm-eabi/4.3.1/libgcc.a”, on line 117 and 132
   Thanks

5. Great. works like a charm.
   @Dorian: thanks for the correction.

6. Hi,
   I have the environment for building a C code for android 1.0 in the ubuntu machine. Now I have downloaded Android 1.5 SDK for linux and want to compile the same C code for Android 1.5. What changes I have to make ?

7. Hi,
   I am using android X86 (taken on 10 oct ’09).
   I get: adb: not found

   Then. I’ve mounted the resulted system.img, copied explicit the *hello in
   /system/bin and data/, then I’ve build the iso and boot it up.
   I can see my hello, but.

   #./hello
   hello: not found

   #hello
   hello: not found

   #adb
   adb not found

   The shell is dumb or….

8. hi marius,
   what output do you get from ls -l
   ?
   also, what do you mean by “then I’ve build the iso and boot it up.”

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10. I did exactly the same as mentioned here but keep on getting the following error:

    “/mydroid/out/target/product/generic/obj/lib/crtbegin_dynamic.o: In function `_start’:
    bionic/libc/arch-arm/bionic/crtbegin_dynamic.S:(.text+0x14): undefined reference to `main’
    collect2: ld returned 1 exit status”

    Any idea how to resolve it?

    Thanks in Advance.

11. Make sure you’ve put the following folders in the path:

    $DROID/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1

    $DROID/prebuilt/linux-x86/toolchain/arm-eabi-4.3.1

12. The both folders are in the path but I am still getting the same error. It was working well few months back but now when I tried again I am getting the above error.

13. Hey, that’s really great! Just checked it out and it worked … now I can port all my ancient C programms to android lol

14. Hey there Tayefeh, funny to see that isn’t it?
    The truth is you can make sore very powerful apps using the JNI.
    I’ve implemented a complete bluetooth l2cap interface for Java using it. Will post more soon.

15. I like the idea, cool!

16. Very nice explanation! you saved my time. All in one place solution! Thanks!

17. I’m glad you like it. Make sure you read about JNI as well: it provides some more options.

18. One more thing – I’m trying to run a sample ‘hello world’ program using a .cpp file instead of .c file. Compiler complains of not finding iostream.h. Could you tell me how to use your script to call a c++ file?

19. Thanks for taking the time to provide this information 😉 It’s most helpful

20. You’re welcome, a .

21. Can you write the same agcc script for mips based system?

22. May I ask, what MIPS android hardware do you have?

23. I have MIPS Malta board with MIPSr2

24. I already have android running on it but my 3rd party software which is generally used in glic environment will not work under bionic based android. So I was wondering can we make such wrapper for mips based systems.

    -Kaushik

25. Can,t install additional packages of android in ubuntu 10.4

26. Hi Radu! Nice guide, but i have a problem with the agcc compiler:

    ~$ agcc helloword.c -o helloword
    arm-eabi-gcc: /home/tanisdlj/mydroid/prebuilt/linux-x86/toolchain/arm-eabi-4.3.1/lib/gcc/arm-eabi/4.2.1/interwork/libgcc.a: No such file or directory

    This is my PATH:

    tanisdlj@tanisdlj-andev:~$ echo $PATH
    /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/home/tanisdlj/bin/:/home/tanisdlj/mydroid/prebuilt/linux-x86/toolchain/arm-eabi-4.3.1/bin:/home/tanisdlj/:/home/tanisdlj/mydroid/

    I follow your guide step by step, but i have this problem. Any suggestion? >.<

27. Hi Radu

    I followed all the steps and in the final step
    agcc hello.c -o hello I get this error

    /localhome/user/bin/mipsandroid/prebuilt/linux-x86/toolchain/arm-eabi-4.3.1/bin/../lib/gcc/arm-eabi/4.3.1/../../../../arm-eabi/bin/ld: /localhome/user/bin/mipsandroid/out/target/product/generic/obj/lib/crtbegin_dynamic.o: Relocations in generic ELF (EM: 8)
    /localhome/user/bin/mipsandroid/prebuilt/linux-x86/toolchain/arm-eabi-4.3.1/bin/../lib/gcc/arm-eabi/4.3.1/../../../../arm-eabi/bin/ld: /localhome/user/bin/mipsandroid/out/target/product/generic/obj/lib/crtbegin_dynamic.o: Relocations in generic ELF (EM: 8)
    /localhome/user/bin/mipsandroid/out/target/product/generic/obj/lib/crtbegin_dynamic.o: could not read symbols: File in wrong format
    collect2: ld returned 1 exit status

    I have set the PATH too correctly. Kindly please help me.

28. /localhome/user/bin/mipsandroid/prebuilt/linux-x86/toolchain/arm-eabi-4.3.1/bin/../lib/gcc/arm-eabi/4.3.1/../../../../arm-eabi/bin/ld: /localhome/user/bin/mipsandroid/out/target/product/generic/obj/lib/crtbegin_dynamic.o: Relocations in generic ELF (EM: 8 )
    /localhome/user/bin/mipsandroid/prebuilt/linux-x86/toolchain/arm-eabi-4.3.1/bin/../lib/gcc/arm-eabi/4.3.1/../../../../arm-eabi/bin/ld: /localhome/user/bin/mipsandroid/out/target/product/generic/obj/lib/crtbegin_dynamic.o: Relocations in generic ELF (EM: 8 )
    /localhome/user/bin/mipsandroid/out/target/product/generic/obj/lib/crtbegin_dynamic.o: could not read symbols: File in wrong format
    collect2: ld returned 1 exit status

29. sabin
    I installed in ubuntu 10.04 and now I can compile c files for android donut 1.6
    if you want I can explain

30. I compiled a test.c for and run on adb shell but how to run on my android phone?(DSTL1)

31. hello , please do, I think that will help the community.

32. mavci, you can use the terminal application for android.

33. thanks Radu!
    I will write all explainations tomorrow.

34. Ok, then I can add them to this post, so others can use it too.

35. this is so dope. I can compile all kinds of console programs now!

    Dude, you rock!

36. @Tanis: you mixed-up your EABI versions in your PATH; there are references to 4.2.1 and 4.3.1

37. glad you like it, Quincy .

38. Can’t seem to get the gpg –import section to work. How exactly do you paste the key in?

39. This tutorial is cool, but I have problems when I try to compile static

    when I add -static directive I get error: “cannot find -lc” “collect2: ld returned 1 exit status”

    do you know how to solve this problem? Thanks

    regards

40. Gcc 4.3 is required for building android. 4.4 has strict has more strict rules so it will through fprintf declaraion errors..

    To fix,

    $ sudo apt-get install gcc-4.3 g++-4.3
    $ sudo rm /usr/bin gcc
    $ sudo rm /usr/bin g++
    $ sudo ln -s gcc-4.3 gcc
    $ sudo ln -s g++-4.3 g++

41. Hello Anup, Thanks for your contribution!

42. I am not at all a technical person, so when it comes to understanding code, this feels foreign to me. However, from what I’ve read, you’ve found a way to include blue tooth functionality with C++? That’s actually kind of cool in my opinion. If you don’t have bluetooth, you make it yourself.

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44. See this NDK/JNI tutorial as well:

    http://www.pocketmagic.net/?p=1332

45. Hi, Thanks for the great tutorial, it worked like a charm. I’m having trouble using GDB. I want to know the loaction of the system and exit call addresses, using the command “p system”. GDB keeps giving me an error “no symbol table”. I’ve gave GDB the correct paths before attching to the process and used the “shared” command. I’m really struggling, Has anyone got any clue to why this is happening.

46. Slightly off-topic, but not really. You talked about implementing a bluetooth L2CAP interface for Java. I have done something similar and am trying to open a L2CAP socket to listen for incoming connections. But when I try to bind to a native L2CAP socket using JNI, I get error code 13 (permission denied) returned to me. When I try the same thing using RFCOMM, it is successful.

    I’m interested in your interface that you wrote and I’m curious if it behaves the same.

47. Hi Greg, yes I’ve used JNI (and some other attempts) to open a L2CAP server socket and it failed on most of the Firmware versions.

    However it works on older Android OS versions (< 1.5), also on newer versions depending on the channel you want to open. What do you mean by "I try the same thing using RFCOMM"?

48. I noticed that the Android API has support for L2CAP (all the way down to the native code), but it all marked private. So I attempted to access the private stuff via reflection and it works great for opening up L2CAP sockets to other devices. But when trying to open a server socket, it fails. I was thinking maybe I was doing something wrong, so I used the same technique for opening an RFCOMM server socket (basically use TYPE_RFCOMM instead of TYPE_L2CAP). I realize that the public API has support for this, but I was trying to prove that using the reflection technique also works, and it does.

    So my conclusion was that L2CAP server sockets must not be supported. And your findings seem to support that theory. Have you investigated any further to figure out where the permission problem is coming from? Do you think this was a bug introduced in 1.5? Or is it an intentional security feature? I’m trying to open up L2CAP server sockets on psm 0x11 and 0x13.

49. Hi Greg, I’m not sure about that. Can you post the code as you did the reflection approach for accessing the private l2cap methods? I would give it a run on my side too.

    Also I need to ask, if you open two PSM sockets with L2CAP, how can you do the same with RFCOMM? Does it work for you?

50. When I say RFCOMM works, I meant that creating the RFCOMM server socket and calling bindListen() on it (all via reflection of course) returns error code 0. I didn’t actually service any incoming connections, but I’m assuming the socket was open and listening. However calling bindListen() on an L2CAP server socket returns error code 13. Same code, just a different type constant passed into the BluetoothServerSocket constructor. I don’t have access to my code right now, but I will post it as soon as I can!

51. Here is my code. Not sure how well this will copy into the browser. Should be pretty easy to follow, just invoke the public static method. Let me know how it works!

    public class BluetoothFactory {
    	
    	public static BluetoothServerSocket createL2CAPBluetoothServerSocket(int psm) {
    		return createBluetoothServerSocket(3 /*TYPE_L2CAP*/, false, false, psm);
    	}
    	
    	private static BluetoothServerSocket createBluetoothServerSocket(int type, boolean auth, boolean encrypt, int port) {
    		try {
    			Constructor constructor = BluetoothServerSocket.class.getDeclaredConstructor(int.class, boolean.class, boolean.class, int.class);
    			constructor.setAccessible(true);
    			BluetoothServerSocket serverSocket = constructor.newInstance(type, auth, encrypt, port);
    			bindListen(serverSocket);
    			return serverSocket;
    		} catch (Exception e) {
    			throw new RuntimeException("unable to create BluetoothServerSocket", e);
    		}
    	}
    	
    	private static void bindListen(BluetoothServerSocket serverSocket) throws SecurityException, IllegalArgumentException, NoSuchFieldException, IllegalAccessException, NoSuchMethodException, InvocationTargetException {
    		BluetoothSocket socket = getSocket(serverSocket);
    		
    		Method bindListenMethod = BluetoothSocket.class.getDeclaredMethod("bindListen");
    		bindListenMethod.setAccessible(true);
    		int errno = ((Integer)bindListenMethod.invoke(socket)).intValue();
    		if (errno != 0) {
    			try {
    				serverSocket.close();
    			} catch(IOException e) {}
    			throwErrnoNative(socket, errno);
    		}
    	}
    	
    	private static BluetoothSocket getSocket(BluetoothServerSocket serverSocket) throws SecurityException, NoSuchFieldException, IllegalArgumentException, IllegalAccessException {
    		Field mSocketField = BluetoothServerSocket.class.getDeclaredField("mSocket");
    		mSocketField.setAccessible(true);
    		return (BluetoothSocket)mSocketField.get(serverSocket);
    	}
    	
    	private static void throwErrnoNative(BluetoothSocket socket, int errno) throws SecurityException, NoSuchMethodException, IllegalArgumentException, IllegalAccessException, InvocationTargetException {
    		Method throwErrnoNativeMethod = BluetoothSocket.class.getDeclaredMethod("throwErrnoNative", int.class);
    		throwErrnoNativeMethod.setAccessible(true);
    		throwErrnoNativeMethod.invoke(socket, errno);
    	}	
    }
    

52. I’ve reformatted the code using the <.pre lang="java"> tag. I will try this code soon, please give me some time.

    Hope there is a simple solution.

53. Hi Radi,
    Nice Post.
    I have written a small program that retrieves the time from a daytime server (time.nist.gov).
    Thru adb shell it runs fine.
    I need a mechanism to execute it without the use of adb, preferably directly on the device.

    Cheers,
    Earlence

54. hi Earlence.

    To execute a native executable, do the following:

    // android.os.Exec is not included in android.jar so we need to use reflection.
        Class execClass = Class.forName("android.os.Exec");
        Method createSubprocess = execClass.getMethod("createSubprocess",
                String.class, String.class, String.class, int[].class);
        Method waitFor = execClass.getMethod("waitFor", int.class);
        
        // Executes the command.
        // NOTE: createSubprocess() is asynchronous.
        int[] pid = new int[1];
        FileDescriptor fd = (FileDescriptor)createSubprocess.invoke(
                null, "/system/bin/ls", "/sdcard", null, pid);
    

    Instead of /system/bin/ls use your Own path to your executable.
    The second string (/sdcard) is a parameter you can send to your executable. For mre info read about android.os.Exec and createSubprocess.

    To read the response of your native executable, you can do something like:

    FileInputStream in = new FileInputStream(fd);
        BufferedReader reader = new BufferedReader(new InputStreamReader(in));
        String output = "";
        try {
            String line;
            while ((line = reader.readLine()) != null) {
                output += line + "\n";
            }
        } catch (IOException e) {
            // It seems IOException is thrown when it reaches EOF.
        }
        
        // Waits for the command to finish.
        waitFor.invoke(null, pid[0]);
    
    

    That’s it. Credits go to http://gimite.net/en/index.php?Run%20native%20executable%20in%20Android%20App

55. Thanks!

56. Im getting a class not found exception. how can I get rid of that problem?

57. please post the complete error details, including the line where you get the error.

58. Class execClass = Class.forName(“android.os.Exec”);

    Cannot find class “Exec”.
    If I put an empty stub (android.os.Exec) – This allows proper compilation and linking, but at runtime, android prevents loading of android.os.* classes which are not in the public SDK. that solves the problem, but then an error comes up on line

    Method createSubprocess = execClass.getMethod(“createSubprocess”,
    String.class, String.class, String.class, int[].class);
    Surely, this is not the correct technique to get rid of the error.

    What are your suggestions?

    Cheers,
    Earlence

59. Does anyone know of a tablet running 2.2 or is flash capable?

60. Hi Greg,

    I now have some time to look over this, looking at the code I see it uses reflection to use the access the private BluetoothServer socket methods.

    To save time, could you post the BluetoothClient socket part as well? I would like to run a quick test on my android.

61. Greg,

    10-21 19:53:03.119: ERROR/AndroidRuntime(855): Uncaught handler: thread main exiting due to uncaught exception
    10-21 19:53:03.159: ERROR/AndroidRuntime(855): java.lang.RuntimeException: unable to create BluetoothServerSocket
    10-21 19:53:03.159: ERROR/AndroidRuntime(855):     at tt.bluetoothtest.BluetoothFactory.createBluetoothServerSocket(BluetoothFactory.java:48)
    10-21 19:53:03.159: ERROR/AndroidRuntime(855):     at tt.bluetoothtest.BluetoothFactory.createL2CAPBluetoothServerSocket(BluetoothFactory.java:34)
    10-21 19:53:03.159: ERROR/AndroidRuntime(855):     at tt.bluetoothtest.BluetoothTest.doBluetoothTest(BluetoothTest.java:44)
    10-21 19:53:03.159: ERROR/AndroidRuntime(855):     at tt.bluetoothtest.BluetoothTest.onClick(BluetoothTest.java:83)
    
    

62. Hey Radu, thanks for giving my code a try.

    Is there more to the stack trace? A caused by perhaps? You’ll notice that when I throw the runtime exception, I am wrapping another exception. I’m curious what exeception that is. I’m assuming it’s going to be permission denied error, but I just want to make sure.

    -Greg

63. yes, it seems to be a permission issue:

    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     at java.lang.reflect.Method.invokeNative(Native Method)
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     at java.lang.reflect.Method.invoke(Method.java:521)
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     at dalvik.system.NativeStart.main(Native Method)
    10-21 20:08:34.619: ERROR/AndroidRuntime(914): Caused by: java.lang.reflect.InvocationTargetException
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     at android.bluetooth.BluetoothServerSocket.(BluetoothServerSocket.java:77)
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     at java.lang.reflect.Constructor.constructNative(Native Method)
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     at java.lang.reflect.Constructor.newInstance(Constructor.java:446)
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     at tt.bluetoothtest.BluetoothFactory.createBluetoothServerSocket(BluetoothFactory.java:44)
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     ... 27 more
    10-21 20:08:34.619: ERROR/AndroidRuntime(914): Caused by: java.io.IOException: Operation not permitted
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     at android.bluetooth.BluetoothSocket.initSocketNative(Native Method)
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     at android.bluetooth.BluetoothSocket.(BluetoothSocket.java:142)
    10-21 20:08:34.619: ERROR/AndroidRuntime(914):     ... 31 more
    
    

    any idea how to overcome this?

64. complete trace:

    10-21 20:25:14.169: ERROR/AndroidRuntime(946): Uncaught handler: thread main exiting due to uncaught exception
    10-21 20:25:14.199: ERROR/AndroidRuntime(946): java.lang.RuntimeException: unable to create BluetoothServerSocket
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at tt.bluetoothtest.BluetoothFactory.createBluetoothServerSocket(BluetoothFactory.java:48)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at tt.bluetoothtest.BluetoothFactory.createL2CAPBluetoothServerSocket(BluetoothFactory.java:34)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at tt.bluetoothtest.BluetoothTest.doBluetoothTest(BluetoothTest.java:54)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at tt.bluetoothtest.BluetoothTest.onClick(BluetoothTest.java:93)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.view.View.performClick(View.java:2364)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.view.View.onKeyUp(View.java:4004)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.widget.TextView.onKeyUp(TextView.java:4369)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.view.KeyEvent.dispatch(KeyEvent.java:1061)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.view.View.dispatchKeyEvent(View.java:3702)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:748)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:748)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:748)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:748)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchKeyEvent(PhoneWindow.java:1655)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at com.android.internal.policy.impl.PhoneWindow.superDispatchKeyEvent(PhoneWindow.java:1102)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.app.Activity.dispatchKeyEvent(Activity.java:2038)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1631)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.view.ViewRoot.deliverKeyEventToViewHierarchy(ViewRoot.java:2368)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.view.ViewRoot.handleFinishedEvent(ViewRoot.java:2338)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1641)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.os.Handler.dispatchMessage(Handler.java:99)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.os.Looper.loop(Looper.java:123)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.app.ActivityThread.main(ActivityThread.java:4363)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at java.lang.reflect.Method.invokeNative(Native Method)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at java.lang.reflect.Method.invoke(Method.java:521)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at dalvik.system.NativeStart.main(Native Method)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946): Caused by: java.lang.reflect.InvocationTargetException
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at android.bluetooth.BluetoothSocket.throwErrnoNative(Native Method)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at java.lang.reflect.Method.invokeNative(Native Method)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at java.lang.reflect.Method.invoke(Method.java:521)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at tt.bluetoothtest.BluetoothFactory.throwErrnoNative(BluetoothFactory.java:78)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at tt.bluetoothtest.BluetoothFactory.bindListen(BluetoothFactory.java:64)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     at tt.bluetoothtest.BluetoothFactory.createBluetoothServerSocket(BluetoothFactory.java:45)
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     ... 27 more
    10-21 20:25:14.199: ERROR/AndroidRuntime(946): Caused by: java.io.IOException: Permission denied
    10-21 20:25:14.199: ERROR/AndroidRuntime(946):     ... 33 more
    
    

    ( on g1 with android 2.1)

65. I was hoping you would know! 🙂

    Your stack trace is different from mine and shows that you are failing in a different place. You are failing in initSocketNative(). On my device, initSocketNative() succeeds. But the later call to bindListenNative() fails with permission denied. Perhaps this is just a difference in devices. Are you testing on an HTC device by any chance? I know HTC has some differences in bluetooth. I am testing on a Moto Droid.

66. yes, I’m testing on a G1 . I’ll try to look over the native code, maybe there’s a clue on what goes wrong

67. Interesting. Your complete stack trace matches mine exactly, but the partial one didn’t. That’s strange that it’s different now. Ok, so we fail in the same place. At least we are consistent! Now to figure out why bindListenNative() returns the permission denied error.

68. Actually that was my mistake, for the first trace , the test app did not have the bluetooth permissions in the AndroidManifest.XML file. So I corrected that, and the second trace is ok.

69. Greg, please do a few tests on your side:

    try to open a different port, other than 0x11 or 0x13

    -if this works then-

    find /system/lib/bluez-plugin/input.so on your Android device, and rename it to something else. Reboot and try opening 0x11 or 0x13 again. Does this work?

70. I tried ports 0x1 and 0x2. Neither worked, same permission denied error. I also renamed input.so to input.so.bak and tried again on port 0x11, permission denied. I rebooted and tried again, same error.

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72. This tutorial is cool, but I have problems when I try to compile static when I add -static directive I get error: “cannot find -lc” “collect2: ld returned 1 exit status”do you know how to solve this problem? Thanks

73. This tutorial rocks! Thank you for posting this kind of stuff 🙂

74. Ubuntu in virtual machine?
    I think you are doing this wrong

75. Very interesting. I think that the link for the “Android Source Code” in step 2 is broken. This link may help:

    http://source.android.com/source/downloading.html

76. Yes! Finally someone writes about linux tutorial.

77. Your technology blog is really very informatic. Thanks ..

78. Thanks so much for this post.