Q22015: SHELL "PATH=\…" Affects Only a Local Copy of DOS

Article: Q22015
Product(s): See article
Version(s): 2.00 2.01 3.00 4.00 4.00b 4.50
Operating System(s): MS-DOS
Keyword(s): ENDUSER | | mspl13_basic
Last Modified: 31-JAN-1990

SHELLing to the DOS PATH command fails to change the default directory
search path when you exit QuickBASIC. BASICA Version 3.10 behaves
similarly.

The following is an example:

   SHELL "PATH=\BASIC"

According to Page 458 of the "Microsoft QuickBASIC Compiler" manual
for Version 3.00 and Page 396 of the "Microsoft QuickBASIC Version
4.0: BASIC Language Reference" manual, the SHELL statement allows
execution of DOS commands such as DIR, PATH, and SORT.

When you invoke a SHELL command from a QuickBASIC program, a local
copy of COMMAND.COM and the DOS environment is spawned. When paths are
changed, only the local environment copy is changed, not the original
DOS environment.

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