A convention for -file

[Moderator, John Quarterman]

[ I'm not positive anything in this article has not been said before,
but it's a useful summary.  -mod ]

From: nike!pyramid!pyrtech!trwrb!desint!geoff (Geoff Kuenning)
Date: Wed, 29 Oct 86 01:02:04 pst
Organization: SAH Consulting, Manhattan Beach, CA

In article <6110 at ut-sally.UUCP> weemba at brahms.berkeley.edu (Matthew P Wiener)
writes:

> Date: Fri, 24 Oct 86 14:27:50 PDT
> Organization: University of California, Berkeley
> 
> In article <6029 at ut-sally.UUCP> Mark Horton writes:
> >	Since many commands take names beginning with "-" as flags,
> >		file names beginning with "-" don't always work.
> 
> There's a real easy fix to the current random collection of special
> flags that handle filenames beginning with a dash: always interpret
> two dashes at the beginning of a command line argument as the name for
> the file obtained by eliding the two dashes into one.  Thus

There're at least two reasons not to do this:  (1) it's unnecessary, and
(2) it conflicts with the standard already established for getopt(3).

It's unnecessary because you can *always* specify a file beginning with
"-" as "./-file".  I find this much easier to remember.

The second reason is that getopt(3) already explicitly defines an argument
of "--" as delimiting the end of the switches.  It is provided specifically
to handle the case when an argument begins with a dash.

Thus, for example, to grep(1) for commands that take a "-i" switch, we
would use:

	egrep -- -i /usr/man/u_man/man1/*

(Note that this applies only on System V;  BSD uses an older convention.
Also note that some System V documentation incorrectly lists the obsolete
"-e" switch for this purpose;  "-e" doesn't work, but "--" does.)
-- 

	Geoff Kuenning
	{hplabs,ihnp4}!trwrb!desint!geoff

Volume-Number: Volume 8, Number 27