[Linux-parport] Checking for bidirectional support

[Jason Curl]

Hello,

I've scrounged through the web, and I can't find a reliable way in my code to
test if the ioctl(fd, PPDATADIR, &dir) will set the parallel port to read.

As far as I know, all my ports support ECP, etc. and I've configured them as
such.

I get PCSPP, TRISTATE, EPP in the kernel messages when ppdev starts (it's a
loadable module). When I enable ECP from the BIOS, I get PCSPP, TRISTATE.

I don't see anything obvious in ppdev.h or parport.h that indicates there is
bidirectional support.

Thanks in advance,
Jason.