[GRASS-dev] Discussing new GUI toolkit: v.pydigit

[Glynn Clements]

Jachym Cepicky wrote:

> > What's the problem with writing to a file, anyhow?
> > 
> 
> I thing, it is slow. Correct me, if I'm false. 

If anything, writing to a file will normally be faster than writing to
a pipe. An application can write the entire image to a file in one go,
but you can't write more than a fixed amount (typically 4Kbytes) to a
pipe at a time.

Unless the system is particularly low on RAM, the application doesn't
have to wait for the data to be physically written to disk. If the
reader deletes the file once it has been read, the data will typically
never be written to disk.

However, it's unlikely that I/O between the PNG driver and the
application is likely to be a signficant factor for performance.

-- 
Glynn Clements <glynn at gclements.plus.com>