Make a copy of the memory on the pointer?

Good day! The problem is this: there is a pcap_t * variable that points to the first byte of the piece of memory where the .pcap file was placed after it was opened. I want to process this traffic and install a filter on it, everything is successful. Only then it is impossible to return to the initial traffic in the program, because a filter is installed on it and in general it is already processed by a loop (the processing function did not drop). The question is how in the function (see readDnsPacket), where the filter itself is installed, throw a copy of the traffic, not the original. This is necessary in order to continue to have the opportunity to work with the original in the program. PS: close and reopen the pcap does not offer))) sorry that I explain so dreary! here is a partial code:

pcap_t* traffic; if ((traffic = pcap_open_offline(path, nullptr)) == nullptr) { std::cout << "Error open traffic file! \n"; system("pause"); return 0; } readDnsPacket(traffic); 

Function readDnsPacket:

 inline void readDnsPacket(pcap_t* traffic) { struct bpf_program fp; char *str = "udp and src port 53"; //filter for dns-response pcap_compile(traffic, &fp, str, 1, 0xffffff); pcap_setfilter(traffic, &fp); pcap_loop(traffic, 0, PacketHandler, nullptr); }