Develop Reference

Building an android-ndk-r17c standalone toolchain with Cygwin

I would like to import the library libsndfile. According to it's doc I need a standalone toolchain for this. Now I'm trying to build said toolchain with Cygwin as described in the official guide but get the error message:
Unsupported platform: CYGWIN_NT-10.0.
I am new to android development and must admit that I struggle with the official guide quite a bit. From what I understand the --arch argument refers to the system I'm building for and the --api argument to the (minimum?) Android version it is running. Which toolkit exactly it is should be irrelevant at this point as long as they are compatible. So for now let's go with --arch x86_64 and --api 21. Overall the in- and output look as follows:
$ ./build/tools/make_standalone_toolchain.py --arch x86_64 --api 21 -v --install-dir ../toolchains/oboe_record_proto/
Unsupported platform: CYGWIN_NT-10.0

This may not be a satisfying answer but here what worked for me in the end:
According to the comment by matzeri, Cygwin is not supported (anymore). My attempts to solve it with Mingw / Msys as suggested were without success either.
Ths, I installed python under Windows and ran the script from the Windows command line.
python .\build\tools\make_standalone_toolchain.py --arch x86_64 --api 21 -v --install-dir ..\toolchains\oboe_record_proto
The toolchain was generated as expected.

How do you define the NDK installation that ndk-build uses?

How do you define the NDK installation that ndk-build uses? I used the r10e build for a good while, then updated my NDK and modified my $PATH to point to the new location, but when I build using the ndk-build command in Terminal it still uses the older android-ndk-r10e version.
I know this because I use the NDK_LOG=1 option when invoking ndk-build and it produces the following verbose information as it builds my project. Notice the references to "/NDKDev/android-ndk-r10e". That's my old installation.
~/Documents/MyNDKProject-- $ ndk-build NDK_LOG=1
HOST_OS=darwin
HOST_ARCH=x86_64
HOST_TAG=darwin-x86_64
GNUMAKE=/Users/user1/Documents/NDKDev/android-ndk-r10e/prebuilt/darwin-x86_64/bin/make (NDK prebuilt)
Android NDK: NDK installation path auto-detected: '/Users/user1/Documents/NDKDev/android-ndk-r10e'
Android NDK: GNU Make version 3.81 detected
Android NDK: Host OS was auto-detected: darwin
Android NDK: Host operating system detected: darwin
Android NDK: Host CPU was auto-detected: x86
Android NDK: HOST_TAG set to darwin-x86
Android NDK: Host tools prebuilt directory: /Users/user1/Documents/NDKDev/android-ndk-r10e/prebuilt/darwin-x86_64/bin
Android NDK: Host 'echo' tool: echo
. . .
Also note that when I enter echo $PATH at the Terminal prompt it gives:
/opt/local/bin:/opt/local/sbin:/usr/bin:/bin:/usr/sbin/:/sbin:/usr/local/bin:/Applications/android-sdk-macosx/ndk-bundle:/Applications/android-sdk-macosx
and where you see /Applications/android-sdk-macosx/ndk-bundle is exactly where it used to refer to the android-ndk-r10e path, so I'm certain I've updated my PATH successfully. So anyhow, IF the PATH environment variable is not what ndk-build uses to determine the NDK installation to use, what does it use, and how can I modify it so that it uses my new installation which is at:
/Applications/android-sdk-macosx/ndk-bundle

Fixed. The problem was that when the .bash_profile file is successfully sourced in a given Terminal session it does not have any effect on other instances of Terminal that are open. I had two instances of Terminal open and because I hadn't closed the one with which I was calling ndk-build the changes to .bash_profile weren't being applied.

android NDK - make standalone toolchain fails

I tried to make a standalone Android NDK toolchain on Linux 64 bit:
~/build/android-ndk-r9/build/tools $ ./make-standalone-toolchain.sh --platform=android-14 --ndk-dir=/home/user/build/android-ndk-r9 --system=linux-x86_64 --install-dir=/home/user/build/android-14-toolchain
Auto-config: --toolchain=arm-linux-androideabi-4.6
Copying prebuilt binaries...
No files are actually copied. Something goes wrong. The NDK ist the latest release r9.
How can I run the script so that the files get copied to the installation directory?

A suggestion: Use the --verbose option if you haven't already done so; it will tell you in which stage the error occurs.
Here are the options I ran to make a standalone toolchain targeting android-14 and arm-linux-androideabi-4.7
sudo sh make-standalone-toolchain.sh --verbose --toolchain=x86-4.7\
--install-dir=/project/arm-cc --ndk-dir=/project/android/ndk/android-ndk-r9\
--platform=android-14

porting libimobiledevice to android

I want to port libimobiledevice to android with ndk in order to make android device enable to communicate with iphone, and import data from iphone to android device. i found this project use autoconf. so i made cross compile use following command
./configure --build=x86_64-pc-linux-gnu --host=arm-linux-androideabi --target=arm-linux-androideabi CPPFLAGS="-I$ANDROID_NDK/platforms/android-14/arch-arm/usr/include -I$ANDROID_NDK/sources/cxx-stl/gnu-libstdc++/include -I$ANDROID_NDK/sources/cxx-stl/gnu-libstdc++/libs/armeabi/include -I$ANDROID_NDK/sources/crystax/include" CFLAGS="-nostdlib" LDFLAGS="-Wl,-rpath-link=$ANDROID_NDK/platforms/android-14/arch-arm/usr/lib -L$ANDROID_NDK/platforms/android-14/arch-arm/usr/lib" LIBS="-lc"
but run into some error, can't find pthread python.
checking for pthread_create, pthread_mutex_lock in -lpthread... no
configure: error: libpthread is required to build libimobiledevice
checking for a version of Python >= '2.1.0'... yes
checking for the distutils Python package... yes
checking for Python include path... -I/usr/include/python2.7
checking for Python library path... -L/usr/lib/python2.7 -lpython2.7
checking for Python site-packages path... /usr/lib/python2.7/site-packages
checking python extra libraries... -ldl
checking python extra linking flags...
checking consistency of all components of python development environment... no
configure: error:
Could not link test program to Python. Maybe the main Python library has been
installed in some non-standard library path. If so, pass it to configure,
via the LDFLAGS environment variable.
Example: ./configure LDFLAGS="-L/usr/non-standard-path/python/lib"
============================================================================
ERROR!
You probably have to install the development version of the Python package
for your distribution. The exact name of this package varies among them.
============================================================================

NDK - Error trying to generate a build.xml file for Hello-jni

I just installed Android NDK, r5b, and while trying to follow the steps from Exploring the hello-jni Sample, on the command line I receive the error:
MacBook-2:~ mvermant$ cd ndk/samples/hello-jni
MacBook-2:hello-jni mvermant$ android update project -p . -s
-bash: android: command not found
I'm using Eclipse Helios release 2 with Android SDK r10 and ADT 10.0.0 on MAC 10.6.6. I have also checked to have GNU Make 3.81, and installed GNU Awk(though I am not sure it's in the right place).
I've searched a lot, and seems there might be a class path missing somewhere, but I can't figure out where exactly and what to do to fix it.

You should make sure the tools directory of your android-sdk is on your (shell) path.
Something like:
export PATH="/path/to/sdk/tools:$PATH"
before you execute your command.
In general you will also need two other directories to be on your path:
/path/to/sdk/platform-tools - for adb and other android sdk tools
/path/to/ndk - for ndk-build and ndk-gdb, which are ndk tools
You can also do some setup so that you don't have to run these commands every time you open Terminal.