Creating TDMS Waveform File using DDC_ functions in C 6.0?

Question

I am trying to implement an export written in C 6.0. I can make TDMS files using the DDC_ commands without any problem. But I cant figure out how to make waveform TDMS files. I figured if I added the wf_ properties I should be able to set the waveform=Yes. But it appears to be more complicated than that.
Here is what I have working so far ... (excluding the error handling to make it easier to see)
DDC_CreateFile(sDestFileName, "TDMS", gszinfoline1, gszinfoline2, gszinfoline3, gszinfoline4, &hOutputFile);
DDC_AddChannelGroup(hOutputFile, szGROUP_NAME, szGROUP_DESC, &hgroup)
DDC_CreateChannelGroupPropertyTimestampComponents(​hgroup,
                                                                      szCHANNEL_NAME,
                                                                      (unsigned int)year,
                                                                      (unsigned int)month,
                                                                      (unsigned int)days,
                                                                      (unsigned int)hours,
                                                                      (unsigned int)minutes,
                                                                      (unsigned int)wholeseconds,
                                                                      (double)fractionseconds);
DDC_AddChannel(hgroup, DDC_Double, szCHANNEL_NAME, szCHANNEL_DESC, szCHANNEL_UNITS, &lphchannel);
DDC_CreateChannelProperty (lphchannel,"wf_increment", DDC_Double, dInterval);
DDC_CreateChannelProperty (lphchannel,"wf_xname", DDC_String, "Time");
DDC_CreateChannelProperty (lphchannel,"wf_xunit_string", DDC_String, "s");
DDC_CreateChannelProperty (lphchannel,"wf_start_offset", DDC_Double, 0.0);
Any suggestions? (All the details on this in help are either aimed at LV or completely missing)
Thanks much,
Don
Solved!
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Answer 1

Hi Lindsay,
Thank you so much for your reply.
I'm not using CVI, I am using Microsoft C/C++ 6.0.
Everything is fine if I make data TDMS files, but everything I have tried to make a waveform file has failed.
The posted code has error handling cut out and you are right, i was missing the following call at the end.
DDC_SetDataValues(lphchanneltime,  lpthischanneltimesarray,  (unsigned int)(scansinfile/decimationfactor));
This code all works to make a TDMS data file but I have to include a separate time channel to make it graphable (not shown).
I would rather specify the wf_increment and not include the Time channel with time values for each sample.
I would have thought all I need to do is set the waveform property on each channel to yes but nothing I do changes that from "No" to "Yes"
Kind Regards,
Don