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The following codes return system handles in IX:
NQ_Ain ($8600) Applicationapplication enquiry (system use only)
NQ_Khn ($8603) read keyboard handle (use ":INP" device instead)
NQ_Shn ($8606) read screen handle (use ":SCR" device instead)
NQ_Phn ($8609) read printer indirected handle
NQ_Nhn ($860C) read null handle (use ":NUL" device instead)
NQ_Wai ($860F) Whowho am I? (system use only)
NQ_Com ($8612) read comms handle (use ":COM" device instead)
NQ_Ihn ($8615) read IN handle (use ":INP" device instead)
NQ_Ohn ($8618) read read OUT handle (use ":OUT" device instead)
NQ_Rhn ($861B) read read direct printer handle NQ_Voz ($861E) application verifies running OZ version (OZ V4.5 and newer) NQ_Roz ($8621) read OZ revision number (OZ V4.5 and newer) NQ_Btl ($8624) read battery status (OZ V4.5 and newer)
Memory Management
NQ_Mfs ($8900) read free space information (system use only)
NQ_Slt ($8903) read slot type information (system use only)
NQ_Mfp ($8906) get total of free RAM pages in slot (OZ 4.2 and newer)
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