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From: refson@castle.ed.ac.uk (Keith Refson)
Newsgroups: comp.std.c
Subject: Making the preprocessor substitute a '#'
Message-ID: <6261@castle.ed.ac.uk>
Date: 11 Sep 90 17:05:47 GMT
Sender: refson@castle.ed.ac.uk
Reply-To: keith@earth.ox.ac.uk
Organization: Oxford University Earth Sciences Dept.
Lines: 24

Is there any way of defining a macro in an ANSI preprocessor which
substitutes  a '#' plus some other text.  That is, I want to say

#define FOO  # pragma bar

and have FOO replaced by the pragma.  Now *I Know* that substituting
pragmas is not standard and I don't care about that.  It will be
conditionally compiled for one machine only, on which it should work.

The trouble is, of course that an ansi cpp interprets the # as a
stringizing instruction.  Is there any way of escaping it?   I have
found no reference to a backslash escape character in K&R 2.  And
though it works under the gnu cpp, it doesn't on my target machine.

Can this be done?
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