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DJViking

Lurker
Jun 6, 2011
2
0
I'm new to Android and have a few question that didn't get answered by trying to Google it. I have bought my first Android phone (SGS2 of course, after years of being a Symbian fanboy), but have not received it yet.

Edit: Perhaps this thread belongs to the Android Lounge instead of here. Most of the questions are general android question except perhaps the last two.

1. Does everything run on top of Dalvik JVM? At the bottom is the Linux kernel. Then there is a Linux process which runs Dalvik VM. Could for instance Sun's JVM run on a Linux process of its own or another Linux application?

2. Can C/C++ Linux program run on Android? Though compiled for ARM. Android has NDK (Native Development Kit) which allows it to run C/C++ applications inside Android applications, but I'm wondering about running C/C++ applications directly on Android. BusyBox is coded in C, but runs on Android. Is it running directly on the kernel's linux process or within an Android application on Dalvik?

3. The latter(Q2) would indicate that not everything run on top of Dalvik. Otherwise C/C++ programs would not run.

4. Android uses ADB (Android Debug Bridge) for its CLI magic. BusyBox uses Ash. Can one install bash as the default shell, with full GNU Core Utilities commands? Some forum posts indicate that it is possible to install an ARM re-compiled bash version.

5. Android can be rooted by installing applications like Super User or BusyBox that would let the user execute applications as root. That would indicate that there exist a root user, in addition to the actual user. Is this similar to how it is on Linux? Can I define a password for the root user so that no applications can run root directly?

6. Are all user data stored in the database SQLite? User data is accessible through different applications, but how does Android determine access rights to it?

7. I have read that Android applications run on their own Linux process and are assigned a unique user ID. Does this mean that we can run ps to see all running processes or does it act like the Sun JVM just showing each VM process? However looks like different applications can run in the same process. Can these be distinguished or do we just the the once process.

8, Is the camera application (that some have made modifications of) a Google app or Samsung app? Just wondering since the former would allow such modified versions to run on other than Samsung phones, but given that different phones have different camera specs I don't see how this could go well.

9. Can the codes typed in the dialer be executed through a shell instead (adb)?
 
I'm new to Android and have a few question that didn't get answered by trying to Google it. I have bought my first Android phone (SGS2 of course, after years of being a Symbian fanboy), but have not received it yet.

Edit: Perhaps this thread belongs to the Android Lounge instead of here. Most of the questions are general android question except perhaps the last two.

1. Does everything run on top of Dalvik JVM? At the bottom is the Linux kernel. Then there is a Linux process which runs Dalvik VM. Could for instance Sun's JVM run on a Linux process of its own or another Linux application?

2. Can C/C++ Linux program run on Android? Though compiled for ARM. Android has NDK (Native Development Kit) which allows it to run C/C++ applications inside Android applications, but I'm wondering about running C/C++ applications directly on Android. BusyBox is coded in C, but runs on Android. Is it running directly on the kernel's linux process or within an Android application on Dalvik?

3. The latter(Q2) would indicate that not everything run on top of Dalvik. Otherwise C/C++ programs would not run.

4. Android uses ADB (Android Debug Bridge) for its CLI magic. BusyBox uses Ash. Can one install bash as the default shell, with full GNU Core Utilities commands? Some forum posts indicate that it is possible to install an ARM re-compiled bash version.

5. Android can be rooted by installing applications like Super User or BusyBox that would let the user execute applications as root. That would indicate that there exist a root user, in addition to the actual user. Is this similar to how it is on Linux? Can I define a password for the root user so that no applications can run root directly?

6. Are all user data stored in the database SQLite? User data is accessible through different applications, but how does Android determine access rights to it?

7. I have read that Android applications run on their own Linux process and are assigned a unique user ID. Does this mean that we can run ps to see all running processes or does it act like the Sun JVM just showing each VM process? However looks like different applications can run in the same process. Can these be distinguished or do we just the the once process.

8, Is the camera application (that some have made modifications of) a Google app or Samsung app? Just wondering since the former would allow such modified versions to run on other than Samsung phones, but given that different phones have different camera specs I don't see how this could go well.

9. Can the codes typed in the dialer be executed through a shell instead (adb)?

I only read a few of the questions you asked. I'd also recommend posting this on xdaforums. Reason being is that over there, there are A LOT of developers who might have more answers to your technical questions.
 
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