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Posting-Version: version B 2.10.2 9/18/84; site watmath.UUCP
Path: utzoo!watmath!rwwetmore
From: rwwetmore@watmath.UUCP (Ross Wetmore [ICR])
Newsgroups: net.decus
Subject: Re: Favorite operating systems query (UNIX vs VMS flaming!!!)
Message-ID: <1363@watmath.UUCP>
Date: Wed, 9-Jul-86 09:42:01 EDT
Article-I.D.: watmath.1363
Posted: Wed Jul  9 09:42:01 1986
Date-Received: Thu, 10-Jul-86 00:39:05 EDT
References: <486@batcomputer.TN.CORNELL.EDU> <1000@ttrdc.UUCP> <873@rti-sel.UUCP> <1320@psivax.UUCP>
Reply-To: rwwetmore@watmath.UUCP (Ross Wetmore [ICR])
Distribution: net
Organization: U of Waterloo, Ontario
Lines: 29

In article <1320@psivax.UUCP> friesen@psivax.UUCP (Stanley Friesen) writes:
>In article <873@rti-sel.UUCP> rcb@rti-sel.UUCP (Random) writes:
>>
>>>Most Unix programs will print out a line or so of "usage" diagnostics if you
>>>invoke them with bogus arguments.  Do VMS programs do this?
>>>
>>
>>No. VMS programs will not let you invoke them with bogus arguments. Since
>>the arguments are parsed by DCL before the program is invoked, if you give
>>too many parameters or an unknown switch DCL will reject it with an error
>>message that points out the specific problem.
>
>	Oh, *great*:-) How does the DCL parse the arguments for a user
>written application program?? I can't see how it can do this without
>some rather messy interface requirements. 
>
   The first response implicitly assumes that the program has been installed
in the DCL command tables. This provides complete parsing of the command
line with such features as making arguments default, required, optional or
any of the above depending on the presence of arguments given. The user has
complete freedom to create and or add to his own personal version of these
tables or to switch to the system default tables at any time. The interface
is quite straightforward and far more robust/capable than most Unix
programmers are willing to take the time to install.
   Of course their is nothing which prevents the VMS program from taking
the DCL command line and parsing its own arguments as per Unix.
   This is unfortunately one of the VMS strongpoints, and not really an
appropriate target for Unix flamers.