So I tried again with arc running on Racket under Linux. Here's what I found:

  arc> (def readit () (drain (readline (stdin))))
  #<procedure: readit>
  arc> (readit)
  ARR(1)="PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG"

  ARR(2)="         N ARR,FND,I,RSD,RTN,STOP,TXT"

  ARR(3)="         W !!,"PASTE""

  ARR(4)="         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X"

  ARR(5)="         K RSDS"

  ("\nARR(1)=\"PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG\"" "\nARR(2)=\"         N ARR,FND,I,RSD,RTN,STOP,TXT\"" "\nARR(3)=\"         W !!,\"PASTE\"\"" "\nARR(4)=\"         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X\"" "\nARR(5)=\"         K RSDS\"" "\n")
  arc> (= alist (readit))
  ARR(1)="PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG"

  ARR(2)="         N ARR,FND,I,RSD,RTN,STOP,TXT"

  ARR(3)="         W !!,"PASTE""

  ARR(4)="         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X"

  ARR(5)="         K RSDS"

  ("\nARR(1)=\"PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG\"" "\nARR(2)=\"         N ARR,FND,I,RSD,RTN,STOP,TXT\"" "\nARR(3)=\"         W !!,\"PASTE\"\"" "\nARR(4)=\"         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X\"" "\nARR(5)=\"         K RSDS\"" "\n")
  arc> alist
  ("\nARR(1)=\"PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG\"" "\nARR(2)=\"         N ARR,FND,I,RSD,RTN,STOP,TXT\"" "\nARR(3)=\"         W !!,\"PASTE\"\"" "\nARR(4)=\"         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X\"" "\nARR(5)=\"         K RSDS\"" "\n")
  arc> (len alist)
  6
  arc> (def printlst (thelist) (if (is thelist nil) (prn "") (do (prn (car thelist)) (printlst (cdr thelist)))))
  #<procedure: printlst>
  arc> (printlst alist)

  ARR(1)="PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG"

  ARR(2)="         N ARR,FND,I,RSD,RTN,STOP,TXT"

  ARR(3)="         W !!,"PASTE""

  ARR(4)="         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X"

  ARR(5)="         K RSDS"



  ""
  arc>                                                   

I did have to key in Ctrl-D twice to actually get the function to finish reading. Is there a better way to do this?

Thanks for all of the help with this.

By "the issue with the \n" do you mean how each line has a \n at the start? How is this sending data between Windows and Linux, can you elaborate?

Yes, it's weird that you had to hit ctrl-d twice. Thanks. I'll try your example on windows later today.

Both these issues aren't happening for me on linux, so it seems likely to be a windows issue.

Edit: Hmm, I do see a leading empty list at the start when reading stdin:

  arc> (readit)
  abc
  def
  ("" "abc" "def")

Edit 2: The trouble seems to be that the first call to 'readline' receives the 'enter' you hit to type in the command.

  arc> (readline (stdin))
  ""
  arc>

Perhaps I need to check out the community version of arc?

Has anyone figured out a way to compile an arc routine? I saw an earlier thread on it, but no resolution.