qfork()

[Barry Margolin]

Submitted-by: barmar at think.uucp (Barry Margolin)

In article <16213 at cs.utexas.edu> jason at cnd.hp.com (Jason Zions) writes:
>Instead of replacing "executes any code", I think you could just add the
>phrase "which modifies memory or calls any function" and maintain the
>intent. Examining variables doesn't depend upon the virtual memory
>relationship between child and parent, but munging a stack for a function
>call might behave differently and hence must be rendered undefined.

Rather than "modifies memory" I suggest it be "modifies any variables" or
something like it that refers to high-level objects created by the C
program.  Just examining a variable may modify memory; on a stack machine,
comparing a variable with zero generally requires pushing the variable onto
the stack, and even on a register machine loading the variable into a
register might force the register's old value to be written to memory.
--
Barry Margolin, Thinking Machines Corp.

barmar at think.com
{uunet,harvard}!think!barmar

Volume-Number: Volume 22, Number 41