Init: Remove unused variables

For build-system CFLAGS clean-up, fix unused variables.

Use a #define instead of static variable in a header file.

Change-Id: Id47bf38e51644b61a9f3ac1893a16553695f1aac
Merge "Init: Remove unused variables"
Libion: Remove unused variables

For build-system CFLAGS clean-up, fix unused variables.

Fix missing close of file descriptors. Explicitly exit after a fork.

Change-Id: I76affbc8647c3a760ed3cacc7f3ada3f59e283b1
Only Win32 doesn't have writev.

Change-Id: I9b5328cea3c88a75135dcb0711cbb5471e8fa388
Merge "Libion: Remove unused variables"
Merge "Only Win32 doesn't have writev."