[Radiance-general] PFILT is crashing constantly...

[Greg Ward]

Hi Jeffrey,

Pfilt, like many Radiance commands, sends its output to stdout, which 
goes to the terminal if you don't redirect it.  It sounds to me like 
you're running it so:

	% pfilt [options] input.pic

When you should be running it like this:

	% pfilt [options] input.pic > output.pic

The redireciton to output.pic with the '>' syntax is critical.  Without 
it, the binary picture that's produced goes to the terminal, resulting 
in a lot of garbage on your screen.

I admit that it doesn't make a whole lot of sense to send binary 
information to stdout, but this is the way things work best in Unix, 
since you can easily create piped commands, such as sending pfilt 
output to ra_* picture conversion programs, etc., using the '|' syntax.

-Greg

> From: "Jeffrey McGrew" <JMcGrew@huntsmanag.com>
> Date: Wed Sep 10, 2003  9:39:32  AM US/Pacific
>
> I've been having a very strange error,
> one that makes me feel like it's something
> that I'm doing wrong.
> ...
> If PFILT is run by RAD automatically (to turn
> an unfinished render into a .pic) then there
> aren't any problems. But if you run PFILT
> independently, it just starts to spit garbage
> to the term, and continues until it's killed
> off. It does this no matter what options are
> passed to it.