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Q59893: Multithreaded Run-Time Libraries Require 40 File Handles

Article: Q59893
Product(s): See article
Version(s): 5.10 6.00
Operating System(s): OS/2
Keyword(s): ENDUSER | | mspl13_c
Last Modified: 17-JUL-1990

If you are creating an application that uses the multithreaded version
of the run-time library (LLIBCMT.LIB or CRTLIB.DLL), it is not
possible to set the file-handle count lower than 40. This is by design
and may change in a future release of the run-time library.

The DosSetMaxFH() function allows an application to dynamically set
the number of file handles a program requires. It takes one parameter
(the number of handles) and returns success, or one of the following
two errors:

   ERROR_INVALID_PARAMETER
   ERROR_NOT_ENOUGH_MEMORY

However, there is a limitation in the function. It will not allow the
program to reduce the number of file handles, only increase them.

In the case of an application that is linked with CRTLIB.DLL or
LLIBCMT.LIB, the library has already set the file-handle count to 40.
In this case, a call to DosSetMaxFH() with a number less than 40
returns an ERROR_INVALID_PARAMETER value.

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