[REBOL] Buffered file reading
From: mat:eurogamer at: 6-Apr-2001 19:02
I'm making a sort of batch URL mover in Rebol. It will take it's
commands via E-mail and download files from the net and upload them
Naturally we need to use some sort of buffered scheme. I asked about
this before and drew a blank but then I found this document on
Take a look at the following extract;
<-- Cut -->
Transferring large files requires special considerations. You may want
to transfer the file in chunks to reduce the memory required by your
computer and to provide user feedback while the transfer is happening.
Here is an example that downloads a very large binary file in chunks.
inp: open/binary/direct ftp://ftp.site.com/big-file.bmp
out: open/binary/new/direct %big-file.bmp
buffer: make binary! buf-size + 2
while [not zero? size: read-io inp buffer buf-size][
write-io out buffer size
total: total + size
print ["transferred:" total]
<-- Cut -->
Well no, that code obviously wont ever work. (total not initialised)
But it's probably close.
The odd thing is that it only transfers about 200000 and I'm not sure
why that would be. It only seems to read a few K at a time and I've no
idea why size would be zero when the magical number of 200000 is hit.
Mat Bettinson - EuroGamer's Gaming Evangelist with a Goatee
http://www.eurogamer.net | http://www.eurogamer-network.com