问题
When a C function does not accept any arguments, does it have to be declared/defined with a \"void\" parameter by the language rules? PC-Lint seems to have problems when there\'s nothing at all in the argument-list, and I was wondering if it\'s something in the language syntax that I don\'t know about.
Edit: I just found a duplicate (back-dupe? it came first) question, C void arguments, which has more answers and explanations.
回答1:
void means the function does not take any parameters. For example,
int init (void)
{
return 1;
}
This is not the same as defining
int init ()
{
return 1;
}
because in the second case the compiler will not check whether the function is really called with no arguments at all; instead, a function call with arbitrary number of arguments will be accepted without any warnings (this is implemented only for the compatibility with the old-style function definition syntax, pre-ANSI).
回答2:
IIRC func(void) in C will declare a function that takes no parameters whereas func() declares a function that will take any number of parameters. I believe the latter is an artifact coming from pre-ANSI C.
According to Wikipedia here, the declaration func() does basically declare the function "without information about the parameters".
来源：https://stackoverflow.com/questions/1163879/in-c-funcvoid-vs-func