diff --git a/src/sudoku.s b/src/sudoku.s
index d67ab54..4218c02 100644
--- a/src/sudoku.s
+++ b/src/sudoku.s
@@ -64,13 +64,26 @@ GETJCL: PUSH  P,A                      ;Save the register A.
         MOVE  A,[JCL]
         MOVE  A,[BPTR,,JCL]            ;Load the command parameters into A.
         MOVE  B,[BPTR,,FNAME1]         ;Pointer to the first file name.
-        PUSHJ P,TOSIXB                 ;Transfer the first word into FNAME1
+        PUSHJ P,CPSTR                  ;Transfer the first word into FNAME1
         MOVE  B,[BPTR,,FNAME2]         ;Pointer to the second file name.
-        PUSHJ P,TOSIXB                 ;Transfer the second word into FNAME2
+        PUSHJ P,CPSTR                  ;Transfer the second word into FNAME2
         POP   P,B                      ;Restore the B register.
         POP   P,A                      ;Restore the A register.
         POPJ  P,                       ;Return from routine.
 
+;Subroutine to copy a string. Takes a bytepointer in A and B
+;where A is the source and B is the destination. It will stop copying, if
+;the end of the string is reached, or a whitespace is encounterd,
+CPSTR:  PUSH  P,D                      ;Store the contents of register D.
+CPSTLP: ILDB  D,A                      ;Load the next character from A.
+        JUMPE D,CPSTEN                 ;Exit the loop.
+        CAIN  D,40                     ;If the character is whitespace
+        JUMPA CPSTEN                   ;exit the loop.
+        IDPB  D,B                      ;Deposit the charcter at destination.
+        JRST  CPSTLP                   ;Repeat with the next character
+CPSTEN: POP   P,D                      ;Restore the D register.
+        POPJ  P,                       ;Return from function.
+
 ;Subroutine to convert an ASCII string into SIXBIT. Takes a byte
 ;pointer in A and B, where A is the source and B is the destination.
 TOSIXB: PUSH  P,D                     ;Store the contents of register D.