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Two main function

Rex
hai all,
itz just a query,can i have two main function in a C program(1 file)
Nov 14 '05 #1
7 1919

"Rex" <me*******@gmail.com> wrote

hai all,
itz just a query,can I have two main function in a C program(1 file)

NO, because execution starts with main, and ANSI C programs are
single-threaded. Two mains would be ambiguous.

Quite often people need to write a temporary main, for instance to test
portions of code. Just change the name of the old main to "oldmain" and the
function will never be called.
Nov 14 '05 #2
Rex wrote on 13/08/04 :
hai all,
itz just a query,can i have two main function in a C program(1 file)


No. main() is just another function. You can't have 2 functions with
external linkage with the same name in a C program.

--
Emmanuel
The C-FAQ: http://www.eskimo.com/~scs/C-faq/faq.html

"C is a sharp tool"

Nov 14 '05 #3
me*******@gmail.com (Rex) wrote:
itz just a query,can i have two main function in a C program(1 file)


Can you have two foo() functions in a single translation unit? Can you
have two bar() functions? No, and no. Why would main() be any different?

Richard
Nov 14 '05 #4
On Fri, 13 Aug 2004 08:41:21 +0200, Emmanuel Delahaye
<em***@YOURBRAnoos.fr> wrote in comp.lang.c:
Rex wrote on 13/08/04 :
hai all,
itz just a query,can i have two main function in a C program(1 file)


No. main() is just another function. You can't have 2 functions with
external linkage with the same name in a C program.


If they are both in one file (one translation unit), only one of them
needs to have external linkage. But that does not change the other
issue, you can't have two functions with the same name in a single
translation unit, regardless of linkage.

--
Jack Klein
Home: http://JK-Technology.Com
FAQs for
comp.lang.c http://www.eskimo.com/~scs/C-faq/top.html
comp.lang.c++ http://www.parashift.com/c++-faq-lite/
alt.comp.lang.learn.c-c++
http://www.contrib.andrew.cmu.edu/~a...FAQ-acllc.html
Nov 14 '05 #5
No you can't have two.
The main function is the only function in your C code that will be execute.
I imagine that you want to execute two parts of your program (two process)
"at the same time" (i mean, in executing state). It is really simple in
linux but if you are in a windows platoform and in a C program it is not
posible.

Pablo.
Nov 14 '05 #6

"Rex" <me*******@gmail.com> wrote in message
news:f1**************************@posting.google.c om...
hai all,
itz just a query,can i have two main function in a C program(1 file)


Yes, there can be two main functions in a C program. Using preprocessor
directives, only one can be compiled during a single compilation (a/k/a
translation).

Paul
Nov 14 '05 #7
"Paul Heininger" <no****@nowhere.com> writes:
"Rex" <me*******@gmail.com> wrote in message
news:f1**************************@posting.google.c om...
hai all,
itz just a query,can i have two main function in a C program(1 file)


Yes, there can be two main functions in a C program. Using preprocessor
directives, only one can be compiled during a single compilation (a/k/a
translation).


Which means that, in effect, one of them doesn't exist.

--
Keith Thompson (The_Other_Keith) ks***@mib.org <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst>
We must do something. This is something. Therefore, we must do this.
Nov 14 '05 #8

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