Function phper_sys::php_conv_fp

pub unsafe extern "C" fn php_conv_fp(
    format: c_char, 
    num: f64, 
    add_dp: boolean_e, 
    precision: c_int, 
    dec_point: c_char, 
    is_negative: *mut bool_int, 
    buf: *mut c_char, 
    len: *mut usize
) -> *mut c_char