Q68021: LOCK May Fail to Properly Return Error After CHAIN Under OS/2

Article: Q68021
Product(s): See article
Version(s): 7.00 7.10
Operating System(s): OS/2
Keyword(s): ENDUSER | SR# S901205-16 buglist7.00 buglist7.10 | mspl13_basic
Last Modified: 9-JAN-1991

Under MS OS/2, the following program demonstrates how a LOCK statement
can fail to properly give a "Permission Denied" error for a locked
record in a file kept open across a CHAIN. This problem does not occur
under MS-DOS.

Microsoft has confirmed this to be a problem with Microsoft BASIC
Professional Development System (PDS) versions 7.00 and 7.10 for MS
OS/2. We are researching this problem and will post new information
here as it becomes available.

Code Samples
------------

TEST01.BAS
----------

10 ON ERROR GOTO 70
20 OPEN "pippo" FOR RANDOM ACCESS READ WRITE SHARED AS #1 LEN=128
30 LOCK 1, 1
40 CHAIN "TEST02"
70 PRINT ERR; ERL
80 END

TEST02.BAS
----------

10 ON ERROR GOTO 70
20 LOCK 1, 1
30 END
70 PRINT ERR; ERL
80 END

Compile and link the above programs as follows:

  BC /X/LP test01;
  LINK test01;
  BC /X/LP test02;
  LINK test02;

Under MS-DOS, the second (CHAINed) program correctly returns a
"Permission Denied" error (error code 70) for the LOCK statement;
however, under OS/2, this program fails to give an error.

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