Abstract: A method of application program (AP) execution within a computer system (S) comprising an operating system (OS) providing an interface to external events. The operating system is essentially unmodifiable by the application programmer. The application program (AP) has at least one high-level language application program module which is modifiable by the programmer. The operating system (OS) controls the computer most of the time and only intermittently dispatches control to the high-level module, whereby the execution of the application program module is not sequential. The method comprises creating (3-2) a thread for execution; detecting (3-4) a need for an asynchronous operation; in response to a detected need, suspending (3-6) the thread's execution; detecting (3-8) completion of the asynchronous operation; and in response to a detected completion of the asynchronous operation, resuming (3-10) the thread's execution.

Abstract: A keyboard mounted in connection with a circuit board (2) includes a light source (3). A key (1) of the keyboard comprises a key cap (4) and a body part (5) located between the key cap (4) and the circuit board (2). The body part (5) diffusively transmits light. The light source (3) is arranged to conduct light into the body part (5) and to illuminate the key (1). A photoelectric member (6) is mounted on the circuit board (2) under the key (1) and at a distance from the light source (3). There is further arranged a light barrier (7) in connection with the circuit board (2) or with which key (1), the barrier is arranged to shield the photoelectric member (6) from the light of the light source (3) coming from the body part (5) when the key is depressed. The decrease in light provides an electric change (1) in the photoelectric member (6) indicating a depression of the key.