Function linuxcnc_hal_sys::hal_port_peek

pub unsafe extern "C" fn hal_port_peek(
    port: hal_port_t, 
    dest: *mut c_char, 
    count: c_uint
) -> bool

hal_port_peek operates the same as hal_port_read but no bytes are consumed from the input port. Repeated calls to hal_port_peek will return the same data. This function should only be called by the component that owns the IN PORT pin. returns true: count bytes were read into dest false: no bytes were read into dest