Why API ‘nx_web_http_client_response_body_get’ is used in the process of POST (sending date to server)?

For  ‘S5D9_AE_CLOUD2_HTTPS’ sample project (HTTPS client connect to HTTPS server)

 

Why API ‘nx_web_http_client_response_body_get’ is used in the process of POST (sending date to server)? 

( this  API is used inside a ‘get_response’ function, which is a part of the POST process )

 

But, according to ‘r11um0095eu0513-synergy-nx-web-http.pdf’, page 72..

“This service retrieves the next packet of content of the resource requested by the previous nx_web_http_client_get_start() or nx_web_http_client_get_secure_start() call. Successive calls to this routine should be made until the return status of NX_WEB_HTTP_GET_DONE is received.”

It seems this API is used in the process of GET (receiving data from server) not POST.

I got confused here..

very appreciated if someone can enlighten me..