FileToPvsBuf - Floss UDO for writing into a circular fft buffer

Hello Everybody!
I’m digging into the FFT department of Csound right now and i’m still trying to understand some Stuff out of the Floss Manual.
I try to get my head around this UDO:

opcode FileToPvsBuf, iik, kSoop
kTrig, Sfile, iFFTsize, iOverlap, iWinsize, iWinshape xin

iFFTsize = (iFFTsize == 0 ? 1024 : iFFTsize)
iOverlap = (iOverlap == 0 ? 256 : iOverlap)
iWinsize = (iWinsize == 0 ? iFFTsize : iWinsize)

if kTrig == 1 then
	iLen filelen Sfile
	kNumCycles = iLen*kr
	kCycle init 0
	while 	kCycle < kNumCycles do
			aIn soundin Sfile
			fftin pvsanal aIn, iFFTsize, iOverlap, iWinsize, iWinshape
			iBuf, kTim pvsbuffer fftin, iLen+(iFFTsize/sr)
			kCycle += 1

xout iBuf, iLen, kTim

Especially these lines:
kNumCycles = iLen*kr
iBuf, kTim pvsbuffer fftin, iLen+(iFFTsize/sr)

I try to explain what i understand and maybe you can correct me or explain it with your words? This would definitiv help me with understanding this.

kNumCycles = iLenkr → setting the length / duration of the loop to read the whole soundfile into the buffer. iLenkr is the Length of the Soundfile in kCycles?

iBuf, kTim pvsbuffer fftin, iLen+(iFFTsize/sr) → iLen+(iFFTsize/sr) i don’t get this at all. Is just adding something to make the buffer circular and the first value is overwritten?

Maybe someone can help me.

All the best,

Solved via the Csound List!