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Re: [RFC] signal-safe fprintf?
On Thu, Mar 7, 2013 at 1:40 AM, Siddhesh Poyarekar
> Right, mmap is not guaranteed by the standard to be signal safe
> either, but it tends to work in practice compared to malloc.
Agree here, though I'd vote for keeping it as if (buf) munmap(buf) on
the back end. I'd be very happy if we switched to mmap.
> In fact, I just had a quick look at the vfprintf code and I think the
> malloc is not the only problem you'll have to work around. The
> vfprintf code locks the FILE, which can cause a deadlock if a signal
> handler was called with that lock held.
This is true, but as pointed out downthread snprintf is (I think) not
vulnerable to this, though I could be misinterpreting how the