Help on an "if" statement on a numerical value

[sapnsapn]

Hi folks,

I am looking at an application written in C some 10+ years ago. There
is a lot of such if statements:
if (my_number) {....} else {...}
Here, my_number is an unsigned int. What exactly is the "if" looking
for to evaluate? Is it the existence of a numerical value or a non-zero
value or just any positive value? I am not a C programmer by trade and
hence this question.

LOL,
Sapn

[Simon Morgan]

On Fri, 22 Jul 2005 05:01:21 -0700, sapnsapn wrote:

I am looking at an application written in C some 10+ years ago. There is a
lot of such if statements:
if (my_number) {....} else {...}
Here, my_number is an unsigned int. What exactly is the "if" looking for
to evaluate? Is it the existence of a numerical value or a non-zero value
or just any positive value? I am not a C programmer by trade and hence
this question.

Any non-zero value.

[David Resnick]

sa******@hotmai l.com wrote:

Hi folks,

I am looking at an application written in C some 10+ years ago. There
is a lot of such if statements:
if (my_number) {....} else {...}
Here, my_number is an unsigned int. What exactly is the "if" looking
for to evaluate? Is it the existence of a numerical value or a non-zero
value or just any positive value? I am not a C programmer by trade and
hence this question.

LOL,
Sapn

For any variable type, "if (foo)" is the same as
"if (foo != 0)"

That works for ints, pointers, chars, etc. Some (including
me) think that "if (foo)" should be only used for variables being
used as boolean, but that is a style question. I prefer being
explicit,
as in "if (foo != '\0')", or "if (foo != NULL)" or "if (foo != 0)".
But all work the same as "if (foo)".

-David

[sapnsapn]

Thanks!

- Sapn