here it explains how to configure FB to compile for FP10.
But what I've been doing and it worked so far: downloaded the SDK4, extracted it to some folder, say C:\Flex_4_SDK. Then written this BAT file:
to compile a project from this kind of build file (config.xml in the same folder where the BAT file is):
set exec=%sdk% -load-config+=%buildfile% -debug=true -incremental=true -benchmark=false -output=%outputfile%
because all other settings related to the compiler version and new classes are already made to this flex-config file
<?xml version="1.0" encoding="utf-8"?>
(this particular example will compile d:\projectsFP10\src\Main.mxml as the document class of the D:\projectsFP10\bin\testFP10.swf.
I believe that there will be not much difference on Linux, except for backslashes and such.
What I haven't managed is to redirect output to the FD console (and I don't really know how to redirect it to the Eclipse console), so, I use it with Flash Tracer plugin in FF (it reads trace messages from the log file created by the player), but maybe there's a better way to do it, just haven't investigated it enough...
* you don't need this line:
It's the FD tracing utility, but, as I say, I haven't managed to stick it to the player