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Re: EXIT_SUCCESS

From Joe Pfeiffer <pfeiffer@cs.nmsu.edu>
Newsgroups comp.lang.c
Subject Re: EXIT_SUCCESS
Date 2016-07-27 11:20 -0600
Organization A noiseless patient Spider
Message-ID <1binvrf16l.fsf@pfeifferfamily.net> (permalink)
References (13 earlier) <9c263285-548c-4f42-8d54-94ba1c3628ab@googlegroups.com> <nn78qd$h3u$1@dont-email.me> <db999c15-dd8b-4dbe-9f55-936d56ca32c9@googlegroups.com> <87h9bbf8d7.fsf@bsb.me.uk> <X-macro-20160727155357@ram.dialup.fu-berlin.de>

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ram@zedat.fu-berlin.de (Stefan Ram) writes:

> Ben Bacarisse <ben.usenet@bsb.me.uk> writes:
>>Do you know about the X macro trick (it may have a proper name, but
>
>   Know? I /invented/ it!
>
> /* 
> < filename  = [stringcall.c]
>   encoding  = [ANSI_X3.4-1968]
>   notation  = [ISO/IEC 9899:1999 (E)]
>   author    = [Stefan Ram] > */ 
> #include <stdio.h>  /* puts   */
> #include <string.h> /* strcmp */
> #define F(r,n,b) r n b
> #define FUNCTIONS \
> F( void, iota, (){ puts( "Lima" ); } )\
> F( void, zeta, (){ puts( "Zulu"  ); } )\
> /**/
> FUNCTIONS
> #undef F
> #define F(r,n,b) n,
> void( * const function[] )() ={ FUNCTIONS };
> #undef F
> #define F(r,n,b) #n,
> char const * const name[] ={ FUNCTIONS };
> #undef F
> int const top = sizeof name / sizeof 0[ name ];
> void call( char const * const n )
> { for( int i = 0; i < top; ++i )
>   if( !strcmp( n, i[ name ]))i[ function ](); }
> int main( void ){ call( "iota" ); call( "zeta" ); }
>
>   Ok, I found this out by myself, but probably I am neither
>   the only nor the first one, who came up with this idea.
>
>   Maybe one can do this with functions too?
>
> #include <stdio.h>
>
> void( *f )( char const *, int n );
>
> void g()
> { f( "alpha", 2 );
>   f( "beta",  4 ); }
>
> void putstring( char const * const text, int const n )
> { puts( text ); }
>
> void putnumber( char const * const text, int const n )
> { printf( "%d\n", n ); }
>
> int main( void )
> { f = putstring; g();
>   f = putnumber; g(); }
>
> alpha
> beta
> 2
> 4
>
>   See? Yet another invention of mine!
>
>   (I do not remember having seen this trick with functions
>   before, but probably ...)

I did pretty much the same thing for a program's configuration files
once.  I used a macro I called "process" that took information about a
data structure as its arguments.  One source file #defined process as
read_field, another as write_field.  Now my .h file could just "process"
all the fields in order, so any changes I made in the configuration file
format were automatically tracked both reading and writing it.

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EXIT_SUCCESS Real Troll <real.troll@trolls.com> - 2016-07-08 00:00 -0300
  Re: EXIT_SUCCESS luser droog <luser.droog@gmail.com> - 2016-07-07 19:54 -0700
  Re: EXIT_SUCCESS Ian Collins <ian-news@hotmail.com> - 2016-07-08 15:03 +1200
  Re: EXIT_SUCCESS James Kuyper <jameskuyper@verizon.net> - 2016-07-07 23:20 -0400
    Re: EXIT_SUCCESS Richard Heathfield <rjh@cpax.org.uk> - 2016-07-08 10:19 +0100
      Re: EXIT_SUCCESS Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-08 03:25 -0700
        Re: EXIT_SUCCESS Richard Heathfield <rjh@cpax.org.uk> - 2016-07-08 13:49 +0100
        Re: EXIT_SUCCESS Keith Thompson <kst-u@mib.org> - 2016-07-08 08:33 -0700
          Re: EXIT_SUCCESS Gareth Owen <gwowen@gmail.com> - 2016-07-08 18:03 +0100
            Re: EXIT_SUCCESS Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-08 19:11 +0100
              Re: EXIT_SUCCESS "Osmium" <r124c4u102@comcast.net> - 2016-07-08 14:25 -0500
                Re: EXIT_SUCCESS Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-08 20:34 +0100
                Re: EXIT_SUCCESS Ken Brody <kenbrody@spamcop.net> - 2016-07-11 19:10 -0400
                Re: EXIT_SUCCESS Robert Wessel <robertwessel2@yahoo.com> - 2016-07-10 01:21 -0500
                Re: EXIT_SUCCESS Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2016-07-10 16:09 -0600
                Re: EXIT_SUCCESS Keith Thompson <kst-u@mib.org> - 2016-07-10 16:01 -0700
                Re: EXIT_SUCCESS "Osmium" <r124c4u102@comcast.net> - 2016-07-10 18:30 -0500
                Re: EXIT_SUCCESS Keith Thompson <kst-u@mib.org> - 2016-07-10 17:00 -0700
                Re: EXIT_SUCCESS James Kuyper <jameskuyper@verizon.net> - 2016-07-10 22:43 -0400
                Re: EXIT_SUCCESS Siri Cruise <chine.bleu@yahoo.com> - 2016-07-10 22:31 -0700
                Re: EXIT_SUCCESS raltbos@xs4all.nl (Richard Bos) - 2016-07-11 08:24 +0000
                Re: EXIT_SUCCESS Ken Brody <kenbrody@spamcop.net> - 2016-07-11 19:18 -0400
                Re: EXIT_SUCCESS gazelle@shell.xmission.com (Kenny McCormack) - 2016-07-11 00:47 +0000
                Re: EXIT_SUCCESS gordonb.0aikd@burditt.org (Gordon Burditt) - 2016-07-12 18:52 -0500
                Re: EXIT_SUCCESS "James R. Kuyper" <jameskuyper@verizon.net> - 2016-07-12 20:32 -0400
                Re: EXIT_SUCCESS Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2016-07-12 20:59 -0600
                Re: EXIT_SUCCESS gordonb.a2m2l@burditt.org (Gordon Burditt) - 2016-07-13 02:11 -0500
                Re: EXIT_SUCCESS James Kuyper <jameskuyper@verizon.net> - 2016-07-13 11:26 -0400
                Re: EXIT_SUCCESS Keith Thompson <kst-u@mib.org> - 2016-07-13 08:48 -0700
                Re: EXIT_SUCCESS Tim Rentsch <txr@alumni.caltech.edu> - 2016-07-18 09:54 -0700
            Re: EXIT_SUCCESS James Kuyper <jameskuyper@verizon.net> - 2016-07-08 17:46 -0400
              Re: EXIT_SUCCESS Keith Thompson <kst-u@mib.org> - 2016-07-09 13:13 -0700
                Re: EXIT_SUCCESS jgh@mdfs.net - 2016-07-25 04:42 -0700
                Re: EXIT_SUCCESS Richard Heathfield <rjh@cpax.org.uk> - 2016-07-25 13:07 +0100
                Re: EXIT_SUCCESS Udyant Wig <udyant.wig@gmail.com> - 2016-07-25 20:05 +0530
                Re: EXIT_SUCCESS raltbos@xs4all.nl (Richard Bos) - 2016-07-25 16:06 +0000
                Re: EXIT_SUCCESS Richard Heathfield <rjh@cpax.org.uk> - 2016-07-25 17:41 +0100
                Re: EXIT_SUCCESS Keith Thompson <kst-u@mib.org> - 2016-07-25 11:04 -0700
                Re: EXIT_SUCCESS Richard Heathfield <rjh@cpax.org.uk> - 2016-07-25 19:14 +0100
                Re: EXIT_SUCCESS BartC <bc@freeuk.com> - 2016-07-25 22:00 +0100
                Re: EXIT_SUCCESS Richard Heathfield <rjh@cpax.org.uk> - 2016-07-25 22:03 +0100
                Re: EXIT_SUCCESS BartC <bc@freeuk.com> - 2016-07-25 22:41 +0100
                Re: EXIT_SUCCESS jadill33@gmail.com - 2016-07-25 14:50 -0700
                Re: EXIT_SUCCESS Keith Thompson <kst-u@mib.org> - 2016-07-25 15:04 -0700
                Re: EXIT_SUCCESS David Brown <david.brown@hesbynett.no> - 2016-07-26 10:43 +0200
                Re: EXIT_SUCCESS jadill33@gmail.com - 2016-07-25 14:41 -0700
                Re: EXIT_SUCCESS David Brown <david.brown@hesbynett.no> - 2016-07-26 10:59 +0200
                Re: EXIT_SUCCESS jadill33@gmail.com - 2016-07-27 06:20 -0700
                Re: EXIT_SUCCESS Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-27 15:44 +0100
                Re: EXIT_SUCCESS Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-27 16:22 +0100
                Re: EXIT_SUCCESS Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2016-07-27 11:20 -0600
                Re: EXIT_SUCCESS luser droog <luser.droog@gmail.com> - 2016-07-27 15:32 -0700
                Re: EXIT_SUCCESS Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-28 14:47 +0100
                Re: EXIT_SUCCESS Keith Thompson <kst-u@mib.org> - 2016-07-25 08:46 -0700
                Re: EXIT_SUCCESS David Brown <david.brown@hesbynett.no> - 2016-07-26 12:44 +0200
                Re: EXIT_SUCCESS Keith Thompson <kst-u@mib.org> - 2016-07-26 08:24 -0700
                Re: EXIT_SUCCESS David Brown <david.brown@hesbynett.no> - 2016-07-26 19:26 +0200
                Re: EXIT_SUCCESS BartC <bc@freeuk.com> - 2016-07-26 18:03 +0100
              Re: EXIT_SUCCESS Ken Brody <kenbrody@spamcop.net> - 2016-07-11 19:15 -0400
                Re: EXIT_SUCCESS supercat@casperkitty.com - 2016-07-11 16:46 -0700
                Re: EXIT_SUCCESS raltbos@xs4all.nl (Richard Bos) - 2016-07-15 13:51 +0000
                Re: EXIT_SUCCESS supercat@casperkitty.com - 2016-07-15 08:07 -0700
                Re: EXIT_SUCCESS Ken Brody <kenbrody@spamcop.net> - 2016-07-15 14:33 -0400
                Re: EXIT_SUCCESS raltbos@xs4all.nl (Richard Bos) - 2016-07-23 09:07 +0000
                Re: EXIT_SUCCESS Randy Howard <rhoward.mx@EverybodyUsesIt.com> - 2016-07-23 16:44 -0500
                Re: EXIT_SUCCESS Ken Brody <kenbrody@spamcop.net> - 2016-07-25 10:36 -0400
                Re: EXIT_SUCCESS Randy Howard <rhoward.mx@EverybodyUsesIt.com> - 2016-07-25 15:28 -0500
              Re: EXIT_SUCCESS Rosario19 <Ros@invalid.invalid> - 2016-07-18 09:45 +0200
        Re: EXIT_SUCCESS gordonb.bitq1@burditt.org (Gordon Burditt) - 2016-07-08 17:56 -0500
  Re: EXIT_SUCCESS Keith Thompson <kst-u@mib.org> - 2016-07-08 08:35 -0700
    Re: EXIT_SUCCESS luser droog <luser.droog@gmail.com> - 2016-07-31 15:03 -0700
      Re: EXIT_SUCCESS Real Troll <real.troll@trolls.com> - 2016-07-31 18:09 -0400
      Re: EXIT_SUCCESS luser droog <luser.droog@gmail.com> - 2016-07-31 15:36 -0700
      Re: EXIT_SUCCESS James Kuyper <jameskuyper@verizon.net> - 2016-08-01 10:09 -0400

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