====== fack ======
**C → S → C {type:'fack', from:..., to:..., name:..., nr:..., of:...}**

fack – file chunk reception acknowledge. Inform sender [[ixnx:wrtc:rtcgate:file|file chunk]] was received, next chunk can be sent.

arguments:
  * from - name of client sending the acknowledgement
  * to - name of client sending the file
  * name - name of file
  * nr - sequential number of received chunk
  * of - number of chunks constituting the file

optional arguments:
  * c2c - client to client mode:
      * "yes": do not forward message through SIP, only through direct connection to another wrtc client connected to same server

====== see also ======
[[ixnx:wrtc:rtcgate:file|file]]