h6. [[OS SWI Calls]] h6(. » [[OS_UpCall]] h6((. » OS_UpCall 8 h2. OS_UpCall 8 h5. (SWI &33) |_<^{width:4em}. Entry | | |<^. R0 |<^. 8| |<^. R1 |<^. Buffer handle| |<^. R2 |<^. 0| |_<^{width:4em}. Exit | | |<^. R0 |<^. Preserved | |<^. R1 |<^. Preserved | |<^. R2 |<^. Preserved | h4. Use The purpose of this call is to inform your application that a buffer's free space has become less than its specified threshold. h4. Notes The Buffer Manager issues this call when data is inserted into the specified buffer, and the free space becomes less than its current threshold. This call is never issued under RISC OS 2. h4. See also * [[OS_UpCall]]