I only used CCSC for a week, then switched to C/3000.

In the case of FOPEN, knowing C has its own fopen function, I always
change the
name of the intrinsic like the following to help in searching code and
understanding what is really being called.

#pragma intrinsic FOPEN     mpe_fopen
#pragma intrinsic FCLOSE    mpe_fclose

My CCOPTS var is set to "-Aa -C +e -D_SOCKET_SOURCE -D_MPEXL_SOURCE"
After testing, you need to include the "+e" option to allow missing
parameters.
Check in the C manual, I think it does state this about intrinsics.

Keven
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