Re: Find the Data Type of Variable


"chellappa" <N.Chellappa@xxxxxxxxx> wrote in message
news:1138722161.310948.281130@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> Hi All,
> How to find the data type of the variable ?

The C language does not have a facility for doing this.

> is there any libaray
> function avaiable? Because i want create generic data type of some
> operation .

When you create an object, you know its type. E.g.:

int i;
double d;

If you keep track of this information yourself (e.g. with
a 'type flag' or such), you can implement 'generic' types
using a pointer to void (type 'void *'). Use a 'type
flag' to convey type information to a function. This is
how 'printf()' does it (e.g. "%d" in the first argument
tells it that the associated argument is type' int). Of
course things won't work if you don't actually pass the
proper type. IOW, 'void*' is quite useful, but needs
to be used with great care. A sharp, two-edged knife.


-Mike


.

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