/dev/stdin

[Root Boy Jim]

? From: Tom Newcomb <newcomb at cory.berkeley.edu>

? So, if all you want is the TTY input, why not use /dev/tty?  It's worked
? beautifully in all the cases I've tried.  So, what am I missing?  Can anybody
? come up with a case where /dev/stdin would NOT be /dev/tty, besides shell
? scripts? (I already know this won't work for scripts run from a shell whose
? input has been redirected.)  In a C program, also, you can just do an
? fdopen(3) on descriptor 0 (and that ALWAYS works).

The point is that stdin is not always /dev/tty. And not all commands support
the (considered by some) ugly kluge of `-' == stdin.

One guy wanted to print a file, even lines in the first column, odd lines
in the second column; he tried "cat file | pr -2 - -". Unfortunately, pr
does not support `-' as a synonym for stdin. Replacing `-' by `/dev/stdin'
should produce the desired results.

Another (mis?)use is to compile programs from stdin. First, we do
`ln -s /dev/stdin x.c', then `cc -c x.c'. I'm sure one can find really
useful uses for stdin being a real file, but personally, I have never
felt enough need to install it. I'm sure the authors have better arguments.

? Tom Newcomb			| WEST, v.  West is what wabbits do when they
? newcomb at cory.Berkeley.EDU	| 	get tired of wunning awound.

	(Root Boy) Jim Cottrell	<rbj at icst-cmr.arpa>
	National Bureau of Standards
	Flamer's Hotline: (301) 975-5688
	The opinions expressed are solely my own
	and do not reflect NBS policy or agreement
	Careful with that VAX Eugene!