Re: stopgap fix for signal handling during restore_command

On Sun, Feb 26, 2023 at 12:12:27PM -0800, Andres Freund wrote:
> On 2023-02-26 11:39:00 -0800, Nathan Bossart wrote:
>> What precisely did you have in mind?  AFAICT you are asking for a wrapper
>> around write().
> 
> Partially I just want something that can easily be searched for, that can have
> comments attached to it documenting why what it is doing is safe.
> 
> It'd not be a huge amount of work to have a slow and restricted string
> interpolation support, to make it easier to write messages. Converting floats
> is probably too hard to do safely, and I'm not sure %m can safely be
> supported. But basic things like %d would be pretty simple.
> 
> Basically a loop around the format string that directly writes to stderr using
> write(), and only supports a signal safe subset of normal format strings.

Got it, thanks.  I will try to put something together along these lines,
although I don't know if I'll pick up the interpolation support in this
thread.

-- 
Nathan Bossart
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