Caché ObjectScript Reference - InterSystems Documentation

$ZAThe following table shows the meanings of the $ZA bits for magnetic tape I/O. Note the Trapcolumn. The letter Y indicates a error. If you have set the $ZTRAP variable,Caché issues the associated $ZTRAP error code.BitValueTrapMeaningNotes01YLogical Error(mixed Readsand Writes)To switch between reading and writing, eitherClose and then Open the device or issue aForward Space, Backspace, or Rewindcommand.24NWriteProtectedReflects the state of the OPEN or USEread-only parameter at all times. This bitdoes not reflect the state of the tape'sphysical write protection (write ring or writelock) because many versions of UNIX giveno notice of tape write protection until anactual write to tape is attempted. If youattempt to open a write-protected 9-track tapewithout the read-only parameter, Caché setsthis bit and opens the tape as read only. Noerror occurs.38YErrorSummaryThe error summary is the logical OR of allconditions that cause a Caché error (allconditions marked Y under Trap)532NBeginning ofTape [BOT]On UNIX systems this bit is set upon rewind,and cleared when tape is opened.664NOn Line7128YController ordrive error101024NEnd of Tape[EOT]Not supported on most UNIX platforms.1416384YTape MarkCaché sets the Tape Mark bit when itencounters a tape mark on Read, ReadBlock, Forward Space or Backspace. Thissets the Error Summary bit and traps to$ZTRAP on Read, Read Label, and ReadBlock1532768YTape NotReadyCaché ObjectScript Reference 461