Make Utility.Process wrap the parts of System.Process that I use,
and add debug logging to them.
Also wrote some higher-level code that allows running an action
with handles to a processes stdin or stdout (or both), and checking
its exit status, all in a single function call.
As a bonus, the debug logging now indicates whether the process
is being run to read from it, feed it data, chat with it (writing and
reading), or just call it for its side effect.
This should fix OSX/BSD issues with not noticing transfer information
files with kqueue. Now that threads are used, the thread can manage the
transfer slot allocation and deallocation by itself; much cleaner.
Test suite now passes with -threaded!
I traced back all the hangs with -threaded to System.Cmd.Utils. It seems
it's just crappy/unsafe/outdated, and should not be used. System.Process
seems to be the cool new thing, so converted all the code to use it
instead.
In the process, --debug stopped printing commands it runs. I may try to
bring that back later.
Note that even SafeSystem was switched to use System.Process. Since that
was a modified version of code from System.Cmd.Utils, it needed to be
converted too. I also got rid of nearly all calls to forkProcess,
and all calls to executeFile, which I'm also doubtful about working
well with -threaded.
This is necessary to generate events when a file is deleted and immediately
replaced. Otherwise, the cache will have the old file, and so no event
would be generated.
Use of getFileStatus is suboptimal, it would be faster to use
the inode returned by readdir -- but getDirectoryContents does not expose
it, so I'd have to copy and modify a lot of low-level code.
Added a modified System.Cmd.Utils, working around bug #681621
Unfortunatly, the test suite still hangs partway through.
Some of the hangs occur within pOpen3 still. Some of the hangs
do not seem to occur within System.Cmd.Utils at all, but in some other
code.
