Re: vcsa and big endian

[Samuel Thibault <samuel.thibault@ens-lyon.org>]

Samuel Thibault, le Sun 09 Dec 2007 23:50:39 +0100, a écrit :
> Samuel Thibault, le Sun 09 Dec 2007 23:43:49 +0100, a écrit :
> > On big endian machines, /dev/vcsa stores text/attribute bytes in big
> > endian order, while it stores them in little endian order on little
> > endian machines.  Is that expected?
> 
> It looks like ggi considers this as normal.  In any case, the vcsa
> manual page should probably be made more clear ("but including
> attributes" -> "but using unsigned shorts that include attributes" for
> instance).

And the code example should be fixed too:

	   char ch, attrib;

           (void) read(fd, &ch, 1);
           (void) read(fd, &attrib, 1);

should rather be

	   unsigned short s;
	   unsigned char ch, attrib;

	   ...

           (void) read(fd, &s, 2);
	   ch = s & 0xff;
	   attrib = (s >> 8);


The manual page should also mention that when a 512 chars font is
loaded, the 9th bit is in the attrib value, and its position can be
fetched through the VT_GETHIFONTMASK ioctl.

Samuel
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