--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/simtool/apdu.c	Sun Jan 24 00:32:10 2021 +0000
@@ -0,0 +1,33 @@
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <pcsclite.h>
+#include <winscard.h>
+#include "globals.h"
+
+apdu_exchange(cmd_apdu, cmd_apdu_len)
+	u_char *cmd_apdu;
+	unsigned cmd_apdu_len;
+{
+	LONG rv;
+	DWORD dwRecvLength;
+	u_char *sw;
+
+	dwRecvLength = 258;
+	rv = SCardTransmit(hCard, SCARD_PCI_T0, cmd_apdu, cmd_apdu_len, NULL,
+			   sim_resp_data, &dwRecvLength);
+	if (rv != SCARD_S_SUCCESS) {
+		fprintf(stderr, "SCardTransmit: %s\n",
+			pcsc_stringify_error(rv));
+		return(-1);
+	}
+	if (dwRecvLength < 2) {
+		fprintf(stderr,
+		"error: SCardTransmit response is shorter than 2 SW bytes\n");
+		return(-1);
+	}
+	sim_resp_data_len = dwRecvLength - 2;
+	sw = sim_resp_data + sim_resp_data_len;
+	sim_resp_sw = (sw[0] << 8) | sw[1];
+	return(0);
+}