Function switch_event_add_header

pub unsafe extern "C" fn switch_event_add_header(
    event: *mut switch_event_t,
    stack: switch_stack_t,
    header_name: *const c_char,
    fmt: *const c_char,
    ...
) -> switch_status_t

\brief Add a header to an event \param event the event to add the header to \param stack the stack sense (stack it on the top or on the bottom) \param header_name the name of the header to add \param fmt the value of the header (varargs see standard sprintf family) \return SWITCH_STATUS_SUCCESS if the header was added