dom0/meminfo-writer: fork into background after first info sent to qmemman (#635)

misc/meminfo-writer.c

@@ -154,6 +154,17 @@ int main(int argc, char **argv)
 		perror("xs_domain_open");
 		exit(1);
 	}
+	if (argc == 3) {
+		/* if not waiting for signal, fork after first info written to xenstore */
+		n = pread(fd, buf, sizeof(buf), 0);
+		buf[n] = 0;
+		meminfo_data = parse(buf);
+		if (meminfo_data)
+			send_to_qmemman(xs, meminfo_data);
+		if (fork() > 0)
+			exit(0);
+	}
+
 	for (;;) {
 		n = pread(fd, buf, sizeof(buf), 0);
 		buf[n] = 0;