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Q43271: C: Cannot Bind Programs with Increased File Handles

Article: Q43271
Product(s): See article
Version(s): 5.10   | 5.10
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | | mspl13_c
Last Modified: 17-MAY-1989

Microsoft C defaults to making 20 file handles available to an
application. This is the case for both OS/2 and DOS. This number can
be increased by modifying the start-up source code provided with
Optimizing C Version 5.10 and linking in the resulting OBJs. This is
documented in the README.DOC (search for _NFILE_).

However, it is not possible to bind a program that is linked to these
modified OBJs. This is because the protect-mode start up makes a call
to DOSSETMAXFH after being modified. This function is not FAPI (dual
mode) and is not bindable.

To give a program more than 20 file handles under both OS/2 and DOS,
you must create separate EXEs for each environment.

An attempt to bind a program that is linked with modified start up will
produce the following error:

   LINK : error L2029: Unresolved externals:

   DOSSETMAXFH in file(s):
   BV3.OBJ(bindv3)

The start-up files that must be modified to increase the number of
available file handles are CRT0DAT.ASM and _FILE.C.

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