c-variadic.md

c_variadic

The tracking issue for this feature is: #44930

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The c_variadic library feature exposes the VaList structure, Rust's analogue of C's va_list type.

Examples

#![feature(c_variadic)]

use std::ffi::VaList;

pub unsafe extern "C" fn vadd(n: usize, mut args: VaList) -> usize {
    let mut sum = 0;
    for _ in 0..n {
        sum += args.arg::<usize>();
    }
    sum
}