variables scope

[Roman Mashak]

Hello, All!

I wonder about the correctness of the following simple code:

int func(int ii)
{
ii=100;
return 0;
}

int main(void)
{
int ii=1,jj;
jj=func(ii);
return 0;
}

The point I concern is the variable 'ii'. It's declared in main() as well as
func() argument. Is it considered by standard or I should better avoid such
kinds of code?

With best regards, Roman Mashak. E-mail: mr*@tusur.ru

[Allan Bruce]

"Roman Mashak" <mr*@tusur.ru> wrote in message
news:d8***********@relay.tomsk.ru...

Hello, All!

I wonder about the correctness of the following simple code:

int func(int ii)
{
ii=100;
return 0;
}

int main(void)
{
int ii=1,jj;
jj=func(ii);
return 0;
}

The point I concern is the variable 'ii'. It's declared in main() as well
as func() argument. Is it considered by standard or I should better avoid
such kinds of code?

This is fine - no problems as far as the standard goes, stylewise may be
different - but no problems.
Allan

[Christopher Benson-Manica]

Roman Mashak <mr*@tusur.ru> wrote:

int func(int ii)
{
ii=100;
return 0;
}
If you're expecting the value of ii in main() to be changed from 1 to
100 by this code, you are mistaken. Arguments in C are passed by
value.
int main(void)
{
int ii=1,jj;
jj=func(ii);
return 0;
} The point I concern is the variable 'ii'. It's declared in main() as well as
func() argument. Is it considered by standard or I should better avoid such
kinds of code?

As noted, it's correct.

--
Christopher Benson-Manica | I *should* know what I'm talking about - if I
ataru(at)cyberspace.org | don't, I need to know. Flames welcome.

[Lawrence Kirby]

On Fri, 17 Jun 2005 19:49:58 +0900, Roman Mashak wrote:

Hello, All!

I wonder about the correctness of the following simple code:

int func(int ii)
{
ii=100;
return 0;
}

int main(void)
{
int ii=1,jj;
jj=func(ii);
return 0;
}

The point I concern is the variable 'ii'. It's declared in main() as well as
func() argument. Is it considered by standard or I should better avoid such
kinds of code?

This is fine. One of the key features of local function variables
including parameters is that they don't interfere with code outside the
function. So you don't have to worry about name clashes, in fact doing so
might be considered an error.

Lawrence

[Martin Ambuhl]

Roman Mashak wrote:

Hello, All!

I wonder about the correctness of the following simple code:

int func(int ii)
{
ii=100;
return 0;
}

int main(void)
{
int ii=1,jj;
jj=func(ii);
return 0;
}

The point I concern is the variable 'ii'. It's declared in main() as well as
func() argument. Is it considered by standard or I should better avoid such
kinds of code?

The name of a formal parameter of a function has nothing to do with any
object with that name outside of the function.

function (int ii)
{
ii = 100;
return 0;
}

means exactly the same thing as
function (int tickle_my_shoe)
{
tickle_my_shoe = 100;
return 0;
}

whether there are variables elsewhere named either 'ii' or 'tickle_my_shoe'.

For that matter (apart from a possible warning from your compiler if
it's checking for unused arguments), the above are equivalent to

function (int ii)
{
return 0;
}