The system variable _sysbase points to this structure.
typedef struct unsigned short os_entry;entry address (BRA …) unsigned short os_version;OS version void (&sstarf#star;reseth)(void);startaddress of OS-code struct _osheader &sstarf#star;os_beg;base of OS void &sstarf#star;os_end;start of ``free'' ram char &sstarf#star;os_rsv1;default shell char &sstarf#star;os_magic;ptr to GEM-MAGIC var. long os_dat;creation date 0xMMDDYYYY unsigned short os_conf;bit 0 = 1 ⇒ PAL, NTSC otherwise unsigned short os_dosdate;creationdate in TOS form. char &sstarf#star;&sstarf#star;p_root;base of OS pool char &sstarf#star;&sstarf#star;pkbshift;kbd shift state var char &sstarf#star;&sstarf#star;p_run;PID of current proc. char &sstarf#star;p_rsv2;reserved OSHDR