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Date: Thu, 31 May 2001 07:43:04 -0700
From: Don Dugger <dugger@hotlz.com>
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To: j mckitrick <jcm@FreeBSD-uk.eu.org>
Cc: freebsd-questions@freebsd.org
Subject: Re: what's wrong with this macro?
References: <20010531143315.A83651@dogma.freebsd-uk.eu.org> <3B164FDD.B59D380A@hotlz.com> <20010531151330.A84734@dogma.freebsd-uk.eu.org> <3B165467.9B71982@hotlz.com> <20010531153311.A85342@dogma.freebsd-uk.eu.org>
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There are some very important differences. Notice the "do" in front of
the "{".
This defines the block as a "do while" block in the other case it was
just a block which is fine in C++ but not in C.

Don 8)


j mckitrick wrote:
> 
> | you may need to change the CXX or CC to g++ or gcc. Normally this is
> | somewhere in the top of the Makefile.
> 
> And yet *this* excerpt compiles fine:
> 
> dogma:~> cat grr2.c
> #define Q_COMMAND_1(a, b) do { \
>         q_command[0] = '\0'; \
>         strcat(q_command, QUANTUM_PROLOGUE); \
>         strcat(q_command, a); \
>         strcat(q_command, b); \
>         strcat(q_command, QUANTUM_EPILOGUE); \
> } while(0)
> 
> dogma:~> cc grr2.c
> /usr/lib/crt1.o: In function `_start':
> /usr/lib/crt1.o(.text+0x79): undefined reference to `main'
> dogma:~>
> 
> jcm
> --
> "I drank WHAT ?!" - Socrates

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