.if false
==================================================================================
- Copyright (c) 2019 Nokia
- Copyright (c) 2018-2019 AT&T Intellectual Property.
+ Copyright (c) 2019-2020 Nokia
+ Copyright (c) 2018-2020 AT&T Intellectual Property.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
Date 28 January 2019
.fi
-.** if formatting with tfm, the roff.im will cause roff output to be generated
-.** if formatting with pfm, then pretty postscript will be generated
.gv e LIB lib
-.if pfm
- .im &{lib}/generic_ps.im
-.ei
- .gv e OUTPUT_RST use_rst
- .if .ev &use_rst 1 =
- .im &{lib}/rst.im
- .ei
- .im &{lib}/roff.im
- .fi
-.fi
+.im &{lib}/man/setup.im
&line_len(6i)
&space
&ital(Port) is used to listen for connection requests from other RMR based applications.
-The value of &ital(max_msg_size) will be used when allocating zero copy send buffers
-which must be allocated, possibly, prior to the application knowing the actual size of
-a specific message.
+The &ital(max_msg_size) parameter is used to allocate receive buffers and is the
+maximum message size which the application expects to receive.
+This value is the sum of &bold(both) the maximum payload size &bold(and) the maximum
+trace data size.
+This value is also used as the default message size when allocating message buffers.
+Messages arriving which are longer than the given maximum will be dropped without
+notification to the application.
+A warning is written to standard error for the first message which is too large on
+each connection.
+
+&space
+&ital(Flags) allows for selection of some RMr options at the time of initialisation.
+These are set by ORing &cw(RMRFL) constants from the RMr header file. Currently the
+following flags are supported:
+
+&half_space
+&beg_dlist(1i : &bold_font )
+&diitem(RMRFL_NONE)
+ No flags are set.
+
+&half_space
+&diitem(RMRFL_NOTHREAD)
+ The route table collector thread is not to be started. This should only be used
+ by the route table generator application if it is based on RMr.
+
+&half_space
+&diitem(RMRFL_MTCALL)
+ Enable multi-threaded call support.
+
+&half_space
+&ditem(RMRFL_NOLOCK)
+ Some underlying transport providers (e.g. SI95) enable locking to be turned off
+ if the user application is single threaded, or otherwise can guarantee that RMR
+ functions will not be invoked concurrently from different threads. Turning off
+ locking can help make message receipt more efficient.
+ If this flag is set when the underlying transport does not support disabling
+ locks, it will be ignored.
+&end_dlist
+
+&h3(Multi-threaded Calling)
+The support for an application to issue a &ital(blocking call) by the &cw(rmr_call()) function
+was limited such that only user applications which were operating in a single thread
+could safely use the function.
+Further, timeouts were message count based and not time unit based.
+Multi-threaded call support adds the ability for a user application with multiple threads
+to invoke a blocking call function with the guarantee that the correct response message
+is delivered to the thread.
+The additional support is implemented with the &ital(rmr_mt_call()) and &ital(rmr_mt_rcv())
+function calls.
+&space
+
+Multi-threaded call support requires the user application to specifically enable it
+when RMr is initialised.
+This is necessary because a second, dedicated, receiver thread must be started, and
+requires all messages to be examined and queued by this thread.
+The additional overhead is minimal, queuing information is all in the RMr message
+header, but as an additional process is necessary the user application must "opt in"
+to this approach.
&space
&h2(ENVIRONMENT)
&half_space
&beg_dlist(1i : &bold_font )
-&ditem(RMR_SEED_RT)
+&diitem(RMR_SEED_RT)
Assumes this is the filename of the seed route table file to use. In normal situations,
the library will wait for an update from the route table generator (expected within a few seconds
of initialisation) before being able to send messages.
supply it to the library.
&half_space
-&ditem(RMR_RTG_SVC)
+&diitem(RMR_RTG_SVC)
The route table generator assumes that RMr is listening on a well known port (4561) by
default, but this environment variable can be used to change the listening port if
needed.
&ex_end
&h2(SEE ALSO )
+.ju off
rmr_alloc_msg(3),
rmr_call(3),
rmr_free_msg(3),
rmr_get_rcvfd(3),
+rmr_mt_call(3),
+rmr_mt_rcv(3),
rmr_payload_size(3),
rmr_send_msg(3),
rmr_rcv_msg(3),
rmr_tokenise(3),
rmr_mk_ring(3),
rmr_ring_free(3)
-
-
-.qu
+.ju on