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Date: Fri, 30 Jan 2004 07:31:58 +0800
From: David Xu <davidxu@freebsd.org>
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Subject: ptrace_clear_single_step
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Is there any reason that ptrace_clear_single_step is not needed ?
I found that alpha implemented it, but not other architectures.
For multiple threads, debugger need to turn off single step status for
specific thread, I found gdb even hacked it to clear single step flag
in %eflag registers on i386 because kernel does not provide a clean
way to clear it.

David Xu