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c - Need for prefixing a function with (void)

I recently came across a rather unusual coding convention wherein the call for a function returning "void" is prefixed with (void).

e.g.

(void) MyFunction();  

Is it any different from the function call like:

MyFunction();  

Has it got any advantage or is it yet another needless but there coding convention of some sort?

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Some functions like printf() return a value that is almost never used in real code (in the case of printf, the number of characters printed). However, some tools, like lint, expect that if a function returns a value it must be used, and will complain unless you write something like:

int n = printf( "hello" );

using the void cast:

(void) printf( "hello" );

is a way of telling such tools you really don't want to use the return value, thus keeping them quiet. If you don't use such tools, you don't need to bother, and in any case most tools allow you to configure them to ignore return values from specific functions.


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