<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta content="text/html;charset=UTF-8" http-equiv="Content-Type"> </head> <body bgcolor="#ffffff" text="#000000"> Matthew Flatt schreef: <blockquote cite="mid200505231928.j4NJS8OU048745@slow.flux.utah.edu" type="cite"> <pre wrap="">You're right --- it won't work. MzScheme semaphores work only with the MzScheme thread scheduler. You'll need to use whatever synchronization primitives the C thread system provides, and then connect to the MzScheme scheduler through scheme_block_until() or scheme_add_evt(). Matthew </pre> </blockquote> Will this cause problems? "C functions that can invoke MzScheme (and also be invoked by MzScheme) depend on strict function-call nesting. For example, suppose a function F uses an internal stack, pushing items on to the stack on entry and popping the same items on exit. Suppose also that F invokes MzScheme to evaluate an expression. If the evaluate on this expression invoked F again in a new thread, but then returns to the first thread before completing the second F, then F's internal stack will be corrupted." Hans </body> </html>