[plt-scheme] having some trouble compiling reliable version of extension module for mzscheme3m; suggestions?

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Sun Sep 11 12:09:31 EDT 2005

At Fri, 9 Sep 2005 15:46:05 -0700 (PDT), Danny Yoo wrote:
> It's not quite right yet, and it's a bit unstable.  In particular, I'm
> running into issues with mzscheme3m: I see segfaults if I really hammer
> the system call hard.

Sorry - I still haven't updated _Inside PLT MzScheme_ with information
on 3m. I'll try to do that soon (still).

> The segfault appears related to my adding of a call to
> 'scheme_block_until_enable_break' in my linux-sendfile C extension; if I
> comment that out and force my extension to just block on the socket, then
> I don't see the segfault.

When you don't call scheme_block_until_enable_break(), then there's no
possibility for GC during your C code, so that's why it works.

When a GC can happen, then you need to cooperate with the 3m collector
more --- in ways that I really will document soon.


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