[syslinux] COM32

[H. Peter Anvin]

On 06/16/2010 05:04 AM, Gene Cumm wrote:
> 
> Writing to anything on the local filesystem (except the ADV) is the
> invalid argument.  You can't write to the FILE pointer as it points
> towards a file.  I believe you could write to the FILE pointer if it
> pointed towards stdout or stderr.  Some BIOSs are buggy hence writing
> is disabled.
> 

Correct, plus it makes the filesystem code in Syslinux *much* simpler.
Writing to a filesystem means maintaining all the invariants, and also
detecting when something is broken so that we don't end up corrupting a
broken filesystem further.  This is difficult stuff with very serious
consequences for doing it wrong.  For readonly access, the worst thing
that happens is that we don't get the right data.

> There have been discussions on writing to the serial port and a TFTP
> server (PXELINUX only) but I can't be certain of their status.  I know
> HPA implemented something that made collecting a key piece (or set) of
> diagnostic data easier than copying character for character something
> on the screen (purely electronic in some way).

Yes, the "sysdump" utility (com32/sysdump).

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.