Q47990: Possible Causes of "‘__iob’ : Unresolved External"

Article: Q47990
Product(s): See article
Version(s): 5.10
Operating System(s): OS/2
Keyword(s): ENDUSER | SR# G890807-24188 _iob iob | mspl13_c
Last Modified: 16-JAN-1990

When linking with CRTLIB.LIB, the problems listed below can cause the
following message when linking a main program to the C run-time DLL
created as described in the MTDYNA.DOC file supplied with the C
Compiler Version 5.10:

   ....  error : L2029 : '__iob' : unresolved external

The problems that can cause this message include the following:

1. Compiling with the wrong include files. Typically, this involves
   compiling without the /I option, as described in MTDYNA.DOC.

2. Compiling without defining the symbol DLL. DLL must be defined in
   any program that calls the C run-time library DLL.

These options, as well as other important information, are covered in
Section 5.2 of MTDYNA.DOC.

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