host.cc

#include "native_client/src/shared/imc/nacl_imc_c.h"
#include <stdio.h>
#include <string.h>
#include <errno.h>

#define SEL_LDR "tools/sel_ldr_x86_64"
#define IRT "tools/irt_core_x86_64.nexe"
#define APP "a.nexe"

#define NACL_HANDLE_TRANSFER_PROTOCOL 0xd3c0de01

int main(int argc, char** argv)
{
	NaClHandle pair[2];
	printf("Creating sockets\n");
	if (NaClSocketPair(pair))
		return 1;
	printf("Forking\n");
	if (fork() == 0) {
		NaClClose(pair[0]);
		char buffer[100];
		sprintf(buffer, "100:%d", pair[1]);
		execl(SEL_LDR, SEL_LDR, "-B", IRT, "-i", buffer, "--", APP, NULL);
	}
	NaClClose(pair[1]);
	NaClMessageHeader msg;
	NaClIOVec iov[2];
	uint32_t header[4] = {NACL_HANDLE_TRANSFER_PROTOCOL, 0};
	char buffer[100] = "Testing!";
	memset(&msg, 0, sizeof(msg));
	iov[0].base = header;
	iov[0].length = sizeof(header);
	iov[1].base = buffer;
	iov[1].length = sizeof(buffer);
	msg.iov = iov;
	msg.iov_length = 2;
	printf("sent %d\n", NaClSendDatagram(pair[0], &msg, 0));
}

module.cc

#include "native_client/src/shared/imc/nacl_imc_c.h"
#include <stdio.h>
#include <string.h>

int main(int argc, char** argv)
{
	NaClMessageHeader msg;
	NaClIOVec iov;
	char buffer[100] = "ASDF";
	memset(&msg, 0, sizeof(msg));
	iov.base = buffer;
	iov.length = sizeof(buffer);
	msg.iov = &iov;
	msg.iov_length = 1;
	int x = NaClReceiveDatagram(100, &msg, 0);
	char buffer2[100];
	NaClGetLastErrorString(buffer2, sizeof(buffer2));
	printf("%s %d %s\n", buffer, x, buffer2);
}