IVTT recipes

[nablator]

To compile ivtt.c as a C++ source on Windows with Microsoft Visual Studio (2019) I had to change a few things:

hash == 1;
-> it is probably meant to be: hash = 1;

char folname[] = "      ";
-> the string is too short, it should be one character longer to allow folname[in_foli] = 0; when in_foli is 7.

int selpage, selloc;
-> uninitialized int used later, changed to: int selpage, selloc = 0;

char ctest[8] = "#=IVTFF ";
char dtest[8] = "#=VDBTF ";
-> changed to:
const char ctest[9] = "#=IVTFF ";
const char dtest[9] = "#=VDBTF ";

Also I had to add:
#pragma warning( disable : 4996 )
to allow "unsafe" C functions fopen, strcpy