linux - Android privileges to execute native applications? -


i downloaded c4droid app android , running commands through system();. i'm learning somethings work while others don't. of cool stuff don't work , appears due user profile not being given rights execute such commands @ linux os level.

so tried experiment. got special gnu compiler arm processor , compiled simple hello world app. put on phone , tried execute through c4droid app system("./myapp.bin"); . got permission denied message.

so i'm trying understand can , can't on phone paid money for? can execute such hello world app or not? need root access execute application made? there way code run wrapping in android/java code? have go through dalvikvm run?

i'm looking way without rooting or downloading busybox , using su.

many many different issues.

  1. permission denied 1 of few error messages primitive shell knows, , it's used many other types of failures including not finding requested command.

  2. the toolbox suite missing many typical unix commands. people install busybox more comprehensive supplement

  3. some of things may want require permissions shell (or more so, application user id) accounts not have. on emulator or engineering device adb shell run root default, though on 'rooted' device may able root shell.

  4. you not need root access run compiled code, code must have suitable abi, must have it's library dependencies satisfied, , must installed in file executable flag, on partition not mounted non-executable flag. of issues face there glibc (or other) vs android's bionic libc. executable scratch directories vary android version, though private storage area of app option if app sets file world readable , executable.

  5. the usual (and "recommended") means of running native code build shared library linked against android's bionic libc, , call dalvik/java app using jni.


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