redirecting output

[Peter da Silva]

In article <1990Jun29.172429.2818 at zoo.toronto.edu> henry at zoo.toronto.edu (Henry Spencer) writes:
> You have the right idea, but you left something out.  Try this instead:

While picking nits, how about doing it right. There's really no excuse for
not calling perror:

> 	#define	FILENAME	"filename"
> 	if (freopen(FILENAME, "w", stdout) == NULL) {
+		perror(FILENAME);
! 		fprintf(stderr, "Can't re-open standard output -- exiting\n");
> 		exit(1);
> 	}

> God is not on your side; such a call *will* fail eventually.  Life is
> much more pleasant if your code copes properly.

And life is even better if it tells you *why* it fails. If your C runtime
doesn't implement perror, make it. I don't know of any operating system where
you can't at least differentiate between missing files and other errors.

Well, outside the top levels of the orange book, anyway.
-- 
Peter da Silva.   `-_-'
+1 713 274 5180.
<peter at ficc.ferranti.com>