PCAP

change "wlan0" with your interface name, and set the maximum number of packets to be received
build with gcc file.c -lpcap
sudo ./a.out

wireshark out.pcap

#include <pcap.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

pcap_dumper_t *pdump;
void ec_decode(u_char*  prova, const struct pcap_pkthdr *pkthdr, const u_char *pkt)
{
        pcap_dump((u_char*)prova, pkthdr, pkt);
}

int main()
{
char pcap_errbuf[PCAP_ERRBUF_SIZE];
char perrbuf[PCAP_ERRBUF_SIZE];
pcap_t *pcap = NULL;
//pcap_lookupdev(perrbuf) // finds the first suitable interface
pcap = pcap_open_live(/*pcap_lookupdev(perrbuf)*/"wlan0", UINT16_MAX, 1, 0, pcap_errbuf);
if(pcap==NULL)
        printf("\n\nPCAP NULL\n\n");
pdump = pcap_dump_open(pcap, "out.pcap");
if(pcap==NULL)
        printf("\n\nPDUMP NULL\n\n");

// 15 equals 15 packets, -1 equals inf
pcap_loop(pcap, 15, ec_decode, (unsigned char *)pdump);

}