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Q42466: "RETURN Without GOSUB"; Btrieve BTVRFAR Fails with BASIC

Article: Q42466
Product(s): See article
Version(s): 4.00 4.00b 4.50
Operating System(s): MS-DOS
Keyword(s): ENDUSER | SR# S890227-68 B_BasicCom | mspl13_basic
Last Modified: 20-AUG-1990

Btrieve now has a procedure named BTRVFAR, which is intended to allow
Btrieve to access variables outside of the near heap. This procedure
is not compatible with BASIC and may cause the error message "RETURN
without GOSUB" to be displayed, even though no such error exists. In
some cases, the program may work correctly in the trace mode or even
in the normal mode after the program has been run once with the trace
function on.

This information applies to QuickBASIC Versions 4.00, 4.00b, and 4.50,
Microsoft BASIC Compiler Version 6.00 and 6.00b for MS-DOS and MS
OS/2, and Microsoft BASIC PDS Version 7.00 for MS-DOS and OS/2. Please
note that BASIC PDS 7.00 for MS-DOS and has its own ISAM file system,
making Btrieve, a third-party ISAM support product, unnecessary.

This compatibility problem occurs whether executed from within the
QB.EXE environment of QuickBASIC, the QBX.EXE environment of the BASIC
PDS 7.00, or from an executable program compiled with BC.EXE.

The solution to the problem is to use the older Btrieve procedure
named BTRV. Shown below is the only change necessary for most programs
using BTRVFAR to convert them to use BTRV.

Code Example
------------

' This code is incomplete; only the highlights are shown
OPEN "NULL" FOR RANDOM AS #1 LEN = 40
FIELD #1 40 AS A$
OP%=0
BLK$=SPACES(128)
BLEN%= 40
KBUF$ = "FileName"
KNUM% = 0

FCB% = SADD(A$) - 188

'Use:
  CALL BTRV( OP%, STAT%, BLK$, FCB%, BLEN%, KBUF$, KNUM%)
'Instead of:
'  CALL BTRVFAR(OP%,STAT%,BLK$,SADD(A$),VARSEG(A$),BLEN%,KBUF$,KNUM%);

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