SET LIBRARY TO ERROR 
DO CreateTest
ON ERROR DO expectError
USE
= DBSKIP(1)  && _Error() called: no DBF in use
USE test
GO TOP
= DBSKIP(-1)
= DBSKIP(-1)    && _Error() called: at top of file
GO BOTT
= DBSKIP(1)
= DBSKIP(1)  && _Error() called: at bottom of file
ON ERROR
PROCEDURE expectError
   ? "ERROR: " + MESSAGE()
RETURN
PROCEDURE CreateTest
   CREATE TABLE test (ABC C(20))
   APPEND BLANK
   REPLACE ABC WITH "This is record 1"
   APPEND BLANK
   REPLACE ABC WITH "This is record 2"
   APPEND BLANK
   REPLACE ABC WITH "This is record 3"
   APPEND BLANK
   REPLACE ABC WITH "This is record 4"
   GO TOP
RETURN

#include <pro_ext.h>
FAR Example(ParamBlk FAR *pblk)
{
   int RetCode;
   if ((RetCode = _DBSkip(-1, pblk->p[0].val.ev_long)) < 0) {
      _PutStr("\nError encountered in example program.");
      _Error(-RetCode);  // _DBSkip() returns negative error code
   }
   _RetInt(RetCode, 10);
}
FoxInfo myFoxInfo[] = {
   {"DBSKIP", (FPFI) Example, 1, "I"},
};
FoxTable _FoxTable = {
   (FoxTable FAR *) 0, sizeof(myFoxInfo)/sizeof(FoxInfo), myFoxInfo
};