Re: [PATCH] stdio-common: Add the fgetln function

[Paul Eggert <eggert@cs.ucla.edu>]

On 6/24/22 06:01, Florian Weimer wrote:
> We could avoid these
> changes if we resized the buffer to twice the original buffer size.
> Then we'd still maintain buffer read alignment, just with a larger
> buffer.  But that runs counter to the goal of avoiding extra
> allocations.

I'm not quite following. Since there would be just one buffer, that's 
one less memory allocation than the two buffers in the proposal. Yes, 
this single buffer might waste more total space due to the memory 
allocated between the buffer start and the line start. But I doubt 
whether it's worth the CPU time and complexity and data movement merely 
to avoid that space wastage.

If the worry is that a 2x growth factor is overkill, we use a 1.5x 
growth factor (as in Gnulib's xpalloc function). It should be easy to 
maintain buffer read alignment regardless of growth factor.