-
-
.. This work is licensed under a Creative Commons Attribution 4.0 International License.
.. SPDX-License-Identifier: CC-BY-4.0
.. CAUTION: this document is generated from source in doc/src/rtd.
.. To make changes edit the source and recompile the document.
.. Do NOT make changes directly to .rst or .md files.
-
============================================================================================
Man Page: rmr_torcv_msg
============================================================================================
-RMR Library Functions
-============================================================================================
-
-
-NAME
---------------------------------------------------------------------------------------------
+
+
+RMR LIBRARY FUNCTIONS
+=====================
+
+
+
+NAME
+----
+
rmr_torcv_msg
-
-SYNOPSIS
---------------------------------------------------------------------------------------------
-
+
+
+SYNOPSIS
+--------
+
::
-
+
#include <rmr/rmr.h>
+
rmr_mbuf_t* rmr_torcv_msg( void* vctx, rmr_mbuf_t* old_msg, int ms_to );
-
-
-DESCRIPTION
---------------------------------------------------------------------------------------------
-
-The rmr_torcv_msg function will pause for *ms_to*
+
+
+DESCRIPTION
+-----------
+
+The ``rmr_torcv_msg`` function will pause for *ms_to*
milliseconds waiting for a message to arrive. If a message
arrives before the timeout expires the message buffer
returned will have a status of RMR_OK and the payload will
RMR_ERR_TIMEOUT. When a received message is returned the
message buffer will also contain the message type and length
set by the sender. If messages were queued while waiting for
-the response to a previous invocation of rmr_call, the oldest
-message is removed from the queue and returned without delay.
-
-The *vctx* pointer is the pointer returned by the rmr_init
-function. *Old_msg* is a pointer to a previously used message
-buffer or NULL. The ability to reuse message buffers helps to
-avoid alloc/free cycles in the user application. When no
-buffer is available to supply, the receive function will
-allocate one.
-
-RETURN VALUE
---------------------------------------------------------------------------------------------
-
-The function returns a pointer to the rmr_mbuf_t structure
-which references the message information (state, length,
-payload), or a nil pointer in the case of an extreme error.
-
-ERRORS
---------------------------------------------------------------------------------------------
-
+the response to a previous invocation of ``rmr_call,`` the
+oldest message is removed from the queue and returned without
+delay.
+
+The *vctx* pointer is the pointer returned by the
+``rmr_init`` function. *Old_msg* is a pointer to a previously
+used message buffer or NULL. The ability to reuse message
+buffers helps to avoid alloc/free cycles in the user
+application. When no buffer is available to supply, the
+receive function will allocate one.
+
+
+RETURN VALUE
+------------
+
+The function returns a pointer to the ``rmr_mbuf_t``
+structure which references the message information (state,
+length, payload), or a nil pointer in the case of an extreme
+error.
+
+
+ERRORS
+------
+
The *state* field in the message buffer will be one of the
following:
-
-RMR_OK
-
- The message buffer (payload) references the received data.
-
-
-RMR_ERR_INITFAILED
-
- The first call to this function must initialise an
- underlying system notification mechanism. On failure, this
- error is returned and errno will have the system error
- status set. If this function fails to intialise, the poll
- mechansim, it is likely that message receives will never
- be successful.
-
-
-RMR_ERR_TIMEOUT
-
- The timeout expired before a complete message was
- received. All other fields in the message buffer are not
- valid.
-
-
-RMR_ERR_EMPTY
-
- A message was received, but it had no payload. All other
- fields in the message buffer are not valid.
-
-
-
-
-INVAL
-
- Parameter(s) passed to the function were not valid.
-
-
-EBADF
-
- The underlying message transport is unable to process the
- request.
-
-
-ENOTSUP
-
- The underlying message transport is unable to process the
- request.
-
-
-EFSM
-
- The underlying message transport is unable to process the
- request.
-
-
-EAGAIN
-
- The underlying message transport is unable to process the
- request.
-
-
-EINTR
-
- The underlying message transport is unable to process the
- request.
-
-
-ETIMEDOUT
-
- The underlying message transport is unable to process the
- request.
-
-
-ETERM
-
- The underlying message transport is unable to process the
- request.
-
-
-EXAMPLE
---------------------------------------------------------------------------------------------
-
-
-SEE ALSO
---------------------------------------------------------------------------------------------
-
+ .. list-table::
+ :widths: auto
+ :header-rows: 0
+ :class: borderless
+
+ * - **RMR_OK**
+ -
+ The message buffer (payload) references the received data.
+
+ * - **RMR_ERR_INITFAILED**
+ -
+ The first call to this function must initialise an underlying
+ system notification mechanism. On failure, this error is
+ returned and errno will have the system error status set. If
+ this function fails to initialise, the poll mechanism, it is
+ likely that message receives will never be successful.
+
+ * - **RMR_ERR_TIMEOUT**
+ -
+ The timeout expired before a complete message was received.
+ All other fields in the message buffer are not valid.
+
+ * - **RMR_ERR_EMPTY**
+ -
+ A message was received, but it had no payload. All other
+ fields in the message buffer are not valid.
+
+
+Upon return the system error number, *errno* might be set
+with a value that can help to explain the meaning of the
+state indicated in the message. The following are possible:
+
+ .. list-table::
+ :widths: auto
+ :header-rows: 0
+ :class: borderless
+
+ * - **INVAL**
+ -
+ Parameter(s) passed to the function were not valid.
+
+ * - **EBADF**
+ -
+ The underlying message transport is unable to process the
+ request.
+
+ * - **ENOTSUP**
+ -
+ The underlying message transport is unable to process the
+ request.
+
+ * - **EFSM**
+ -
+ The underlying message transport is unable to process the
+ request.
+
+ * - **EAGAIN**
+ -
+ The underlying message transport is unable to process the
+ request.
+
+ * - **EINTR**
+ -
+ The underlying message transport is unable to process the
+ request.
+
+ * - **ETIMEDOUT**
+ -
+ The underlying message transport is unable to process the
+ request.
+
+ * - **ETERM**
+ -
+ The underlying message transport is unable to process the
+ request.
+
+
+
+
+EXAMPLE
+-------
+
+
+
+SEE ALSO
+--------
+
rmr_alloc_msg(3), rmr_call(3), rmr_free_msg(3),
rmr_get_rcvfd(3), rmr_init(3), rmr_payload_size(3),
rmr_rcv_msg(3), rmr_send_msg(3), rmr_rcv_specific(3),
Code Review / ric-plt / lib / rmr.git / blobdiff