[tlbuild] dvi test?

[Bruno Haible]

> > >      3208/0x31ed:  ftruncate(0x6, 0x0, 0x0)		 = 0 0
> > >      3208/0x31ed:  lseek(0x6, 0xFFFFFFFFFFFFF7C7, 0x1)		 = -1 Err#22
> ...
> Note that in this case, it's not ftruncate() that's failing but rather fseek()/lseek(),

This explains now why it's OS dependent: The code is shrinking a file
to length 0, and then asking to move the file descriptor's position
within that file backwards by 2105 bytes.

How about doing things in the opposite order? I.e. move the fseek()
call, that calls lseek(), _before_ ftruncate. Then it should behave well,
independently of the operating system.

Bruno