Rtos API example

Revision:
0:9fca2b23d0ba
diff -r 000000000000 -r 9fca2b23d0ba mbed-os/platform/mbed_poll.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-os/platform/mbed_poll.h	Sat Feb 23 12:13:36 2019 +0000
@@ -0,0 +1,60 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2017 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef MBED_POLL_H
+#define MBED_POLL_H
+
+#define POLLIN         0x0001 ///< Data may be read without blocking
+#define POLLOUT        0x0010 ///< Data may be written without blocking
+#define POLLERR        0x1000 ///< An error has occurred on the device or stream
+#define POLLHUP        0x2000 ///< The device has been disconnected
+#define POLLNVAL       0x4000 ///< The specified file handle value is invalid
+
+namespace mbed {
+
+class FileHandle;
+
+/** \addtogroup platform */
+/** @{*/
+/**
+ * \defgroup platform_poll poll functions
+ * @{
+ */
+
+struct pollfh {
+    FileHandle *fh;
+    short events;
+    short revents;
+};
+
+/** A mechanism to multiplex input/output over a set of file handles(file descriptors).
+ * For every file handle provided, poll() examines it for any events registered for that particular
+ * file handle.
+ *
+ * @param fhs     an array of PollFh struct carrying a FileHandle and bitmasks of events
+ * @param nfhs    number of file handles
+ * @param timeout timer value to timeout or -1 for loop forever
+ *
+ * @return number of file handles selected (for which revents is non-zero). 0 if timed out with nothing selected. -1 for error.
+ */
+int poll(pollfh fhs[], unsigned nfhs, int timeout);
+
+/**@}*/
+
+/**@}*/
+
+} // namespace mbed
+
+#endif //MBED_POLL_H