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Q35906: BC 6.00 Example Calling OS/2 API Function DosSetMaxFH

Article: Q35906
Product(s): See article
Version(s): 6.00 6.00b 7.00
Operating System(s): OS/2
Keyword(s): ENDUSER | | mspl13_basic
Last Modified: 1-FEB-1990

Below is a sample program that makes a call to the MS OS/2 function
DosSetMaxFH. This program can be compiled in Microsoft BASIC Compiler
Versions 6.00 and 6.00b for MS OS/2 and Microsoft BASIC Professional
Development System (PDS) Version 7.00 for MS OS/2.

By default, 20 file handles are allocated to a file. To increase the
number of file handles available, the DosSetMaxFH function must be
called. The maximum number of file handles is 255. When determining
the required number of handles, add several for dynamic-link modules
(these modules use several handles), and three more for the default
system I/O handles.

The following is a code example:

'This information is found in BSEDOSFL.BI
DECLARE FUNCTION DOSSETMAXFH%(BYVAL P1 AS INTEGER)

INPUT "Enter the maximum number of file handles : ",fh%
x=DosSetMaxFH%(fh%)

IF (x) THEN
   Print "An error occurred.  The error number is ";x
ELSE
   Print "Maximum number of file handles has been changed."
END IF

ON ERROR GOTO DONE

for i = 1 to 255
  fl$="xxxxx"+mid$(str$(i),2,len(str$(i)))
  open fl$ for output as i
next i
stop

done:
  Print i

end

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