问题
If I kill an Android app with System.exit(...), does it matter what status code I pass? I couldn't find any documentation on whether Android just ignores it or whether certain ones lead to any error messages for example or have any other meaning.
回答1:
This is the exit code returned by the process when it finishes; Android however does not care, but know that the error code should never be higher then 255.
Here is a list of standard exit codes - some process may use their own codes.
0 Clean Exit
1 General Error Catchall
2 Misuse of shell builtins
126 Command invoked execution error
127 Command not found
128 Invalid exit argument?
130 Termination by Control-C
255 Exit status unknown
回答2:
Android does not care, no. This is a java thing -- you can use them for your own debugging etc etc.
Here's an example of system exit codes: http://www.opensource.apple.com/source/Libc/Libc-320/include/sysexits.h
But pretty much, anything > 0 means that its an abnormal exit. You can set it to whatever you want, but I'd just stick to 0 unless you're interacting with other things.
It just seems to be the accepted convention.
来源：https://stackoverflow.com/questions/30226842/does-android-care-about-exit-status-code-passed-to-system-exit