Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!lll-tis!ames!hao!husc6!bbn!kgregory
From: kgregory@bbn.COM (Keith D. Gregory)
Newsgroups: comp.lang.c
Subject: Re: Pragmas
Message-ID: <5724@ccv.bbn.COM>
Date: 31 Dec 87 18:36:20 GMT
References: <17196@topaz.rutgers.edu> <1620005@hpcilzb.HP.COM>
Reply-To: kgregory@ccv.bbn.com (Keith D. Gregory)
Organization: Bolt Beranek and Newman Inc., Cambridge MA
Lines: 23
Summary: Well, here's what it is - now why do I use it?

In article <1620005@hpcilzb.HP.COM> cr@hpcilzb.HP.COM (Cindy Roberts) writes:
>
>>	What is a pragma, and what is the function of #pragma in C?
>
>I would also like a clue!

A #pragma statement is "a compiler non-specific way of indicating compiler
specific actions". . . a portable way of saying that you have non-portable
code.
  
On the surface, this seems to be a good idea - if your compiler sees a #pragma
that it doesn't recognize, then it abends.  If it does recognize a pragma, then
it may (or may not) shift into a special processing mode.
  
  
Of course, as far as I can tell, there are absolutely no controls on the use
of #pragma directives.  Two compilers could use the same directive to do 
different things (picture #pragma assembly, to indicate the use of inline A/L),
and fail radically when code for one is compiled under the other.
  
So, to all the people "who really know" . . . is there any good reason for
#pragma's existance (I don't consider the above mentioned reason to be "good")
 
-kdg