progids

static VALUE
foletype_s_progids(VALUE self)
{
    HKEY hclsids, hclsid;
    DWORD i;
    LONG err;
    VALUE clsid;
    VALUE v = rb_str_new2("");
    VALUE progids = rb_ary_new();

    err = reg_open_key(HKEY_CLASSES_ROOT, "CLSID", &hclsids);
    if(err != ERROR_SUCCESS) {
        return progids;
    }
    for(i = 0; ; i++) {
        clsid = reg_enum_key(hclsids, i);
        if (clsid == Qnil)
            break;
        err = reg_open_vkey(hclsids, clsid, &hclsid);
        if (err != ERROR_SUCCESS)
            continue;
        if ((v = reg_get_val2(hclsid, "ProgID")) != Qnil)
            rb_ary_push(progids, v);
        if ((v = reg_get_val2(hclsid, "VersionIndependentProgID")) != Qnil)
            rb_ary_push(progids, v);
        RegCloseKey(hclsid);
    }
    RegCloseKey(hclsids);
    return progids;
}