Редактирование данных сетевого пакета.

#include <iostream>

char *StrToHexStr(char *str, int len)
{
char *newstr = new char[(len*2)];
char *cpnew = newstr;
char *cpold = str;

for(int i = 0; i < len; i++){
        sprintf(cpnew, "%02X", (char)(*cpold++));
        cpnew+=2;
}
return newstr;
}

int main(){
    int len = 18;
    char data[30]="binary\0data1234asd";
    char pattern[6+1] = "313233";
    char replaceto[6+1] = "911119";
    char * pFind;
    char * buf = data;
    char * hexstr = StrToHexStr(buf,len);
    std::cout<< "buf in hex - " << hexstr << std::endl;
    pFind = strstr(hexstr,pattern);
    if(pFind)
        std::cout<< "need replace !" << std::endl;
return 0;
}