Desperately need for help to understand C codes

[kickbeer]

Can someone explain me this codes:

/* Instruction emulation. */ This is comment
void __divsi3(void)
{
}

What means by instruction emulation?? why the word void is used 2 times? what does __divsi3 do actually? After that what does this {} do?

 

[_TopGun_]

Find a good book about C++.
It's the only solution.

 

[btbass]

The first 'void' informs the compiler that this function returns nothing.
The second 'void' informs the compiler that this function takes no arguments.

Function return type: 'void' no return type
Function name: '__divsi3'
Function arguments: '(void)' no arguments.

The Braces would normally contain the code that implements the function.

void __divsi3(void)
{
c code to implement function
}

In this case, they contain nothing, so the function does nothing.

The comment

/* Instruction emulation. */

is written by the programmer, normally to make clear what the function does.
So this is meaningless. You could put any old gibberish here, it is ignored by the compiler.
This comment suggests that the function will emulate an assembler instruction, maybe some type of divide routine?

So, to sum up, it does nothing and is meaningless.

If you havnt already done so, get a book on
The C programming language.

 

[siongboon]

Try reading this book.
"C for dummies".

The title is a bit insulting.
But trust me, it is a very well written book.
You will grab a good fundamental from this book.

I used to keep a list of good books,
**broken link removed**