On Fri, Apr 27, 2012 at 9:47 AM, Matt Birkholz <m...@birkholz.chandler.az.us> wrote: >> From: Taylor R Campbell <campb...@mumble.net> >> Date: Thu, 26 Apr 2012 22:01:29 +0000 >> >> Date: Thu, 26 Apr 2012 13:29:33 -0700 >> From: Matt Birkholz <m...@birkholz.chandler.az.us> >> >> > From: "Micah Brodsky" <micah...@csail.mit.edu> >> > Date: Thu, 26 Apr 2012 11:10:47 -0400 >> >> > While you're at it, do be careful about using sockets from multiple >> > threads simultaneously. They're not really thread-safe like native >> > OS sockets are. [...] >> >> Ummm... one should be careful when using ANY resource from multiple >> threads... so Scheme's ports/sockets each come with a mutex... so I >> can only wonder what you're on about... How "really thread-safe" are >> "native OS sockets"? >> >> The mutex in a port is advisory, not mandatory. MIT Scheme uses it >> only to grant ownership of the `console port' to a single thread. >> Concurrent use of a port in two different threads can corrupt its >> internal state. Concurrent use of a file descriptor (or `native OS >> socket', or `channel') from two different threads can't corrupt its in >> internal state. > > You seem to think "native OS sockets" are channels, but Micah is > talking about a Scheme port -- more comparable to a libc "stream", no? > Do the latest libcs ensure putc and getchar are thread-safe? (I hope > not: what a waste!)
Yes, they do. You need putc_unlocked, getchar_unlocked, etc. to skip the mutex, which makes sense to be safe by default. -- Alex _______________________________________________ MIT-Scheme-devel mailing list MIT-Scheme-devel@gnu.org https://lists.gnu.org/mailman/listinfo/mit-scheme-devel
