! Segment 7 I/O layout included
%end %of %list

! Layout of segment 7: ALL I/O status variables live here.
! Hence any process calling   MAP VIRT (this id, 7, 7)  can pick
! up entire state of this process' I/O.
! See e.g. new IMP-77 compiler control process. Each pass maps its
! Seg 7 onto that of control process, and control proc. performs
! all opening/closing of files instead of individual passes. Hence
! less code is required to support each pass, easing shoe-horning
! problems!

%record %format  seg7fm ( %c
   %string(*)%name  param str,    { ->string param from parent via loader }
   %integer   load flag,          { Type of load: generally ignored?      }
   %byte      unit, fsys,         { Current disk + file system number     }
              callid, strm0id,    { Parent task, SER of TTY for this task }
              id, dummy1,         { Real identity of this task            }
   %integer   gvar,               { Var for GOT SYM - makes it go faster  }
   %record(sdfm) %name inx, outx, { -> current stream descriptors         }
   %string(31) prompt,            { Current prompt string                 }
   %byte      int char, dummy2,   { Last int.      Offset=8_60 *CRITICAL* }
   %integer   instrmx, outstrmx,  { Current stream numbers                }
   %record(pf) p,                 { For all I/O Package message passing   }
   %byte %array param space (8_76:8_237), { Covers 8_112:8_237 *CRITICAL* }
   %record(sdfm) %name %array %c
                in  strm (0:max streams), { -> corresponding stream descs }
                out strm (0:max streams), { " "  "  "     "  "    "  "  " }
   %record(sdfm) ttin, ttout,        { TTY I/O stream descriptors         }
   %byte %array tt in  buff (0:127), { TTY I/O buffers                    }
                tt out buff (0:127),
   %record(sbfm) %array  %c
                sb (1:max streams*2) { (Desc+buffer)s for file streams    } %c
)

! Mapped onto virtual store by...
%const %record(seg7fm) %name  S7 == 8_160000

%list
%end %of %file