Receive Messages from Chrome Extension in a C++ program -

i have chrome extension starts executable c++ file using nativehostmessaging through json file points file.

this .exe file tries read messages send extension. first, reads 4 bytes depicts length, reads number of bytes equal length. first thing file wait message extension.

however, executable file did not receive extension , keeps on waiting. nothing exists on stdin(0).

is security issue or doing wrong? did have read/write sequence in wrong order?

here how mine looks windows:

#include "stdafx.h" #include "json\json.h"  int _tmain(int argc, _tchar* argv[]) {      //save in file know called     file *fh_debug; int errorcode;     errorcode =fopen_s(&fh_debug, "debug.txt","ab+");     std::string msg = "host called";     fwrite( msg.c_str(), sizeof(char),msg.size(),fh_debug);      unsigned int uisize = 0;     std::string inputstr;      //read first 4 bytes (=> length)     (int = 0; < 4; i++)     {         int read_char = getchar();         uisize += read_char * (int) pow(2.0, * 8);     }      //for debug "0000" = 808464432     if ( uisize == 808464432 ) {         uisize = 0; inputstr = "{\"text\":\"tester\"}";      }      //debug record size     msg = std::to_string(uisize);     fwrite( msg.c_str(), sizeof(char),msg.size(),fh_debug);      //read text     (unsigned int = 0; < uisize; i++)     {         inputstr += getchar();     }      //debug record json message     msg = inputstr;     fwrite( msg.c_str(), sizeof(char),msg.size(),fh_debug);      //get text     std::string thetext;     json::value jsonroot;     json::reader jsonreader;     bool ok = jsonreader.parse(inputstr, jsonroot);      try {         thetext = jsonroot.get("text", "no text element").asstring();     }     catch (std::exception& e)     {         std::cout << e.what() << '\n';         throw e;     }      //debug record json message     msg = thetext;     fwrite( msg.c_str(), sizeof(char),msg.size(),fh_debug);      std::string strout = "{\"text\":\"hello " + thetext + "\"}";     uisize = strout.length();      msg = strout;     fwrite( msg.c_str(), sizeof(char),msg.size(),fh_debug);      std::cout << char(((uisize>>0) & 0xff));     std::cout << char(((uisize>>8) & 0xff));     std::cout << char(((uisize>>16) & 0xff));     std::cout << char(((uisize>>24) & 0xff));     std::cout << strout.c_str();      return 0; }