libnfc/examples/doc/quick_start_example1.c

#ifdef HAVE_CONFIG_H
  #include "config.h"
#endif // HAVE_CONFIG_H

#include <stdlib.h>
#include <nfc/nfc.h>
#include <nfc/nfc-messages.h>

int main(int argc, const char* argv[])
{
  nfc_device_t* pnd;
  nfc_target_info_t nti;

  // Display libnfc version
  const char* acLibnfcVersion = nfc_version();
  printf("%s use libnfc %s\n", argv[0], acLibnfcVersion);

  // Connect using the first available NFC device
  pnd = nfc_connect(NULL);

  if (pnd == NULL) {
      ERR("%s", "Unable to connect to NFC device.");
      return EXIT_FAILURE;
  }

  // Set connected NFC device to initiator mode
  nfc_initiator_init(pnd);

  // Drop the field for a while
  nfc_configure(pnd,NDO_ACTIVATE_FIELD,false);

  // Let the reader only try once to find a tag
  nfc_configure(pnd,NDO_INFINITE_SELECT,false);

  // Configure the CRC and Parity settings
  nfc_configure(pnd,NDO_HANDLE_CRC,true);
  nfc_configure(pnd,NDO_HANDLE_PARITY,true);

  // Enable field so more power consuming cards can power themselves up
  nfc_configure(pnd,NDO_ACTIVATE_FIELD,true);

  printf("Connected to NFC reader: %s\n",pnd->acName);

  // Poll for a ISO14443A (MIFARE) tag
  if (nfc_initiator_select_tag(pnd,NM_ISO14443A_106,NULL,0,&nti)) {
      printf("The following (NFC) ISO14443A tag was found:\n");
      printf("    ATQA (SENS_RES): "); print_hex(nti.nai.abtAtqa,2);
      printf("       UID (NFCID%c): ",(nti.nai.abtUid[0]==0x08?'3':'1')); print_hex(nti.nai.abtUid,nti.nai.szUidLen);
      printf("      SAK (SEL_RES): "); print_hex(&nti.nai.btSak,1);
      if (nti.nai.szAtsLen) {
	  printf("          ATS (ATR): ");
	  print_hex(nti.nai.abtAts,nti.nai.szAtsLen);
      }
  }

  // Disconnect from NFC device
  nfc_disconnect(pnd);
  return EXIT_SUCCESS;
}