h6. [[OS SWI Calls]] h6(. » [[OS_Word]] h6((. » OS_Word 21 h2. OS_Word 21 h5. (SWI &07) The action performed depends on the reason code value at offset +0 in R1. h4(#reason). Reason Codes |_<^{width:4em}. #|_<^{width:4em}. Hex #|_<^. Action| |<^. 0|<^. &00|<^. [[OS_Word 21_0|Define pointer shape]]| |<^. 1|<^. &01|<^. [[OS_Word 21_1|Define the mouse co-ordinate bounding box]]| |<^. 2|<^. &02|<^. [[OS_Word 21_2|Set mouse multipliers]]| |<^. 3|<^. &03|<^. [[OS_Word 21_3|Set mouse position]]| |<^. 4|<^. &04|<^. [[OS_Word 21_4|Read unbuffered mouse position]]| |<^. 5|<^. &05|<^. [[OS_Word 21_5|Set pointer position]]| |<^. 6|<^. &06|<^. [[OS_Word 21_6|Read pointer position]]| |<^. 7|<^. &07|<^. Read the mouse bounding box (RISCOS Ltd Select only, not implemented on RISC OS 5)| h4. Use The purpose of this call is to provide a number of operations relating to the mouse and pointer. h4. See also * [[OS_Word]]