LIBNFC: Quick start example that presents how to discover a ST SRx tag

st_srx.c

/**
 * @file st_srx.c
 * @brief Quick start example that presents how to discover a ST SRx tag
 */

// To compile this simple example:
// $ gcc -o st_srx st_srx.c -lnfc

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

int
main(int argc, const char *argv[])
{
    nfc_device *pnd;
    nfc_target nt;

    // Allocate only a pointer to nfc_context
    nfc_context *context;

    // Initialize libnfc and set the nfc_context
    nfc_init(&context);
    if (context == NULL) {
        printf("Unable to init libnfc (malloc)\n");
        exit(EXIT_FAILURE);
    }

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

    // Open, using the first available NFC device which can be in order of selection:
    //   - default device specified using environment variable or
    //   - first specified device in libnfc.conf (/etc/nfc) or
    //   - first specified device in device-configuration directory (/etc/nfc/devices.d) or
    //   - first auto-detected (if feature is not disabled in libnfc.conf) device
    pnd = nfc_open(context, NULL);

    if (pnd == NULL) {
        printf("ERROR: %s\n", "Unable to open NFC device.");
        exit(EXIT_FAILURE);
    }
    // Set opened NFC device to initiator mode
    if (nfc_initiator_init(pnd) < 0) {
        nfc_perror(pnd, "nfc_initiator_init");
        exit(EXIT_FAILURE);
    }

    printf("NFC reader: %s opened\n", nfc_device_get_name(pnd));

    // We need first to get the firmware activating the type B by polling for regular Type B tag:
    int res = 0;
    nfc_target ant[1];
    nfc_modulation nm = {
        .nmt = NMT_ISO14443B,
        .nbr = NBR_106,
    };

    nfc_initiator_list_passive_targets(pnd, nm, ant, 1);

    // Poll for a ST SRx tag
    nm.nmt = NMT_ISO14443B2SR;
    if (nfc_initiator_select_passive_target(pnd, nm, NULL, 0, &nt) > 0) {
        char *s;
        str_nfc_target(&s, &nt, true);
        printf("%s", s);
        nfc_free(s);
        printf("\n");
    }
    // Close NFC device
    nfc_close(pnd);
    // Release the context
    nfc_exit(context);
    exit(EXIT_SUCCESS);
}

And how can i get/print the data that on the card?