Re: [cc65] Questions for CBM guys

From: Oliver Schmidt <>
Date: 2008-03-02 13:11:09
Hi everybody,

Please let me summarize what I have learned so far to make sure I got
it right...

- The cc65 C-library POSIX functions allow for 8 open files, 3 being
preopened as stdin, stdout and stderr. Closing those 3 allows for 8
disk files.

- The C64 (and C128 ?) Kernal allows for 15 open files, 2 being
reserved for "stdin" and "stdout". So it allows for 13 disk files.

- Most (propably all) drives allow for 3 open sequential files.

- There are Kernal entry points available both for the C64 and C128 to
allow for direct printing to the screen bypassing the file/channel
abstraction layer.

Overall result:

Even with two drives - or some (hard disk ?) drive with doubled number
of channels: Neither the 8 open files of the C-library nor the 13 open
files of the Kernal are the bottleneck. So there's no real point in
bypassing them for screen output. So I'll just POSIX-close() stdin and
stdout and continue to log to the screen via POSIX-write() to stderr.

Thanks to everybody contributing to this thread, Oliver
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Received on Sun Mar 2 13:11:19 2008

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