int len;
unsigned char* payload;
unsigned char* xaction;
- uint sub_id;
- uint tp_state;
+ int sub_id;
+ int tp_state;
} rmr_mbuf_t;
Messages which are received while waiting for the response
are queued internally by RMR, and are returned to the user
application when rmr_rcv_msg is invoked. These messages are
-returned in th order received, one per call to rmr_rcv_msg.
+returned in the order received, one per call to rmr_rcv_msg.
Call Timeout
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prevent, in most cases, the function from blocking forever.
The timeout period is **not** based on time (calls to clock
are deemed too expensive for a low latency system level
-library, but instead the period is based on the number of
+library), but instead the period is based on the number of
received messages which are not the response. Using a
non-time mechanism for *timeout* prevents the async queue
from filling (which would lead to message drops) in an
Retries
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-The send operations in RMr will retry *soft* send failures
+The send operations in RMR will retry *soft* send failures
until one of three conditions occurs:
2.
- The underlying transport reports a * hard * failure
+ The underlying transport reports a *hard* failure
3.
The maximum number of retry loops has been attempted
-A retry loop consists of approximately 1000 send attemps **
-without** any intervening calls to * sleep() * or * usleep().
-* The number of retry loops defaults to 1, thus a maximum of
+A retry loop consists of approximately 1000 send attempts
+**without** any intervening calls to *sleep()* or *usleep().*
+The number of retry loops defaults to 1, thus a maximum of
1000 send attempts is performed before returning to the user
application. This value can be set at any point after RMr
-initialisation using the * rmr_set_stimeout() * function
+initialisation using the *rmr_set_stimeout()* function
allowing the user application to completely disable retires
(set to 0), or to increase the number of retry loops.
immediately to the user application.
It should be noted that depending on the underlying transport
-mechanism being used, it is extremly possible that during
-normal operations that retry conditions are very likely to
-happen. These are completely out of RMr's control, and there
-is nothing that RMr can do to avoid or midigate these other
-than by allowing RMr to retry the send operation, and even
-then it is possible (e.g. during connection reattempts), that
-a single retry loop is not enough to guarentee a successful
-send.
+mechanism being used, it is extremely likely that retry
+conditions will happen during normal operations. These are
+completely out of RMR's control, and there is nothing that
+RMR can do to avoid or mitigate these other than by allowing
+RMR to retry the send operation, and even then it is possible
+(e.g., during connection reattempts), that a single retry
+loop is not enough to guarantee a successful send.
RETURN VALUE
--------------------------------------------------------------------------------------------
EAGAIN
- The underlying message system wsa interrupted or the
- device was busy; the message was **not** sent, and user
- application should call this function with the message
- again.
+ The underlying message system was interrupted or the
+ device was busy; the message was **not** sent, and the
+ user application should call this function with the
+ message again.
EXAMPLE
--------------------------------------------------------------------------------------------
-The following code bit shows one way of using the rmr_call
-function, and illustrates how the transaction ID must be set.
+The following code snippet shows one way of using the
+rmr_call function, and illustrates how the transaction ID
+must be set.
::
int retry_delay = 50000; // retry delay (usec)
static rmr_mbuf_t* mbuf = NULL; // response msg
msg_t* pm; // private message (payload)
- m// get a send buffer and reference the payload
+ // get a send buffer and reference the payload
mbuf = rmr_alloc_msg( mr, RMR_MAX_RCV_BYTES );
pm = (msg_t*) mbuf->payload;
- p// generate an xaction ID and fill in payload with data and msg type
+ // generate an xaction ID and fill in payload with data and msg type
snprintf( mbuf->xaction, RMR_MAX_XID, "%s", gen_xaction() );
snprintf( pm->req, sizeof( pm->req ), "{ \\"req\\": \\"num users\\"}" );
mbuf->mtype = MT_REQ;
-
msg = rmr_call( mr, msg );
if( ! msg ) { // probably a timeout and no msg received
return NULL; // let errno trickle up
- }
+ }
if( mbuf->state != RMR_OK ) {
while( retries_left-- > 0 && // loop as long as eagain
- errno == EAGAIN &&
- (msg = rmr_call( mr, msg )) != NULL &&
+ errno == EAGAIN &&
+ (msg = rmr_call( mr, msg )) != NULL &&
mbuf->state != RMR_OK ) {
usleep( retry_delay );
}
-
if( mbuf == NULL || mbuf->state != RMR_OK ) {
rmr_free_msg( mbuf ); // safe if nil
return NULL;
NAME
--------------------------------------------------------------------------------------------
-rmr_wh_open
+rmr_close
SYNOPSIS
--------------------------------------------------------------------------------------------
The context (ctx) pointer passed in is the pointer returned
by the call to rmr_init().
-**NOTE:** There is no support for epoll in Nanomsg, thus his
-function is only supported when linking with the NNG version
-of RMr and the file descriptor returned when using the
-Nanomsg verfsion will always return an error.
-
RETURN VALUE
--------------------------------------------------------------------------------------------
The rmr_get_rcvfd function returns a file descriptor greater
-or equal to 0 on success and -1 on error. If this function is
-called from a user application linked against the Nanomsg RMr
-library, calls will always return -1 with errno set to
-EINVAL.
+or equal to 0 on success and -1 on error.
ERRORS
--------------------------------------------------------------------------------------------
rmr_mbuf_t* msg = NULL;
int nready;
int i;
-
mrc = rmr_init( "43086", RMR_MAX_RCV_BYTES, RMRFL_NONE );
rcv_fd = rmr_get_rcvfd( mrc );
-
- rep_fd = epoll_create1( 0 ); _ B ,// initialise epoll environment
+ ep_fd = epoll_create1( 0 ); // initialise epoll environment
epe.events = EPOLLIN;
epe.data.fd = rcv_fd;
epoll_ctl( ep_fd, EPOLL_CTL_ADD, rcv_fd, &epe ); // add our info to the mix
-
while( 1 ) {
- nready = epoll_wait( ep_fd, events, 10, -1 ); // -1 == block forever (no timeout)
- for( i = 0; i < nready && i < 10; i++ ) { // loop through to find what is ready
- if( events[i].data.fd == rcv_fd ) { // RMr has something
+ nready = epoll_wait( ep_fd, events, 10, -1 ); // -1 == block forever (no timeout)
+ for( i = 0; i < nready && i < 10; i++ ) { // loop through to find what is ready
+ if( events[i].data.fd == rcv_fd ) { // RMR has something
msg = rmr_rcv_msg( mrc, msg );
if( msg ) {
// do something with msg
}
}
-
// check for other ready fds....
}
}
ENVIRONMENT
--------------------------------------------------------------------------------------------
-As a part of the initialisation process rmr_init will look
-into the available environment variables to influence it's
-setup. The following variables will be used when found.
+As a part of the initialisation process rmr_init reads
+environment variables to configure itself. The following
+variables are used if found.
RMR_ASYNC_CONN
Allows the async connection mode to be turned off (by
- setting the value to 0. When set to 1, or missing from the
- environment, RMR will invoke the connection interface in
- the transport mechanism using the non-blocking (async)
+ setting the value to 0). When set to 1, or missing from
+ the environment, RMR will invoke the connection interface
+ in the transport mechanism using the non-blocking (async)
mode. This will likely result in many "soft failures"
(retry) until the connection is established, but allows
- the application to continue unimpeeded should the
+ the application to continue unimpeded should the
connection be slow to set up.
RMR_BIND_IF
This provides the interface that RMR will bind listen
- ports to allowing for a single interface to be used rather
- than listening across all interfaces. This should be the
- IP address assigned to the interface that RMR should
- listen on, and if not defined RMR will listen on all
- interfaces.
+ ports to, allowing for a single interface to be used
+ rather than listening across all interfaces. This should
+ be the IP address assigned to the interface that RMR
+ should listen on, and if not defined RMR will listen on
+ all interfaces.
RMR_CTL_PORT
port) was used to define this port. However, a future
version of Route Manager will require RMR to connect and
request tables, thus that variable is now used to supply
- the Route Manager well known address and port.
+ the Route Manager's well-known address and port.
- To maintain backwards compatablibility with the older
- Route Manager versions, the presence of this variable in
- the environment will shift RMR's behaviour with respect to
- the default value used when RMR_RTG_SVC is **not**
- defined.
+ To maintain backwards compatibility with the older Route
+ Manager versions, the presence of this variable in the
+ environment will shift RMR's behaviour with respect to the
+ default value used when RMR_RTG_SVC is **not** defined.
When RMR_CTL_PORT is **defined:** RMR assumes that Route
Manager requires RMR to connect and request table updates
- is made, and the default well known address for Route
+ is made, and the default well-known address for Route
manager is used (routemgr:4561).
When RMR_CTL_PORT is **undefined:** RMR assumes that Route
**Deprecated.** Should be set to 1 if the route table
generator is sending "plain" messages (not using RMR to
- send messages, 0 if the rtg is using RMR to send. The
- default is 1 as we don't expect the rtg to use RMR.
+ send messages), 0 if the RTG is using RMR to send. The
+ default is 1 as we don't expect the RTG to use RMR.
This variable is only recognised when using the NNG
transport library as it is not possible to support NNG
report *ready* until a table is received. The static route
table may contain both the route table (between newrt
start and end records), and the MEID map (between meid_map
- start and end records)
+ start and end records).
RMR_SRC_ID
to the user application with the next invocation of
*rmr_mt_rcv()* or *rmr_rvv_msg().* by RMR, and are returned
to the user application when rmr_rcv_msg is invoked. These
-messages are returned in th order received, one per call to
+messages are returned in the order received, one per call to
rmr_rcv_msg.
-NOTE: Currently the multi-threaded functions are supported
-only when the NNG transport mechanism is being used. It will
-not be possible to link a programme using the Nanomsg version
-of the library when references to this function are present.
-
The Transaction ID
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The user application is responsible for setting the value of
the transaction ID field before invoking *rmr_mt_call.* The
transaction ID is a RMR_MAX_XID byte field that is used to
-match the response message when it arrives. RMr will compare
+match the response message when it arrives. RMR will compare
**all** of the bytes in the field, so the caller must ensure
that they are set correctly to avoid missing the response
-message. (The application which returns the response message
+message. The application which returns the response message
is also expected to ensure that the return buffer has the
matching transaction ID. This can be done transparently if
the application uses the *rmr_rts_msg()* function and does
Retries
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-The send operations in RMr will retry *soft* send failures
+The send operations in RMR will retry *soft* send failures
until one of three conditions occurs:
2.
- The underlying transport reports a * hard * failure
+ The underlying transport reports a *hard* failure
3.
The maximum number of retry loops has been attempted
-A retry loop consists of approximately 1000 send attemps **
-without** any intervening calls to * sleep() * or * usleep().
-* The number of retry loops defaults to 1, thus a maximum of
+A retry loop consists of approximately 1000 send attempts
+**without** any intervening calls to *sleep()* or *usleep().*
+The number of retry loops defaults to 1, thus a maximum of
1000 send attempts is performed before returning to the user
application. This value can be set at any point after RMr
-initialisation using the * rmr_set_stimeout() * function
+initialisation using the *rmr_set_stimeout()* function
allowing the user application to completely disable retires
(set to 0), or to increase the number of retry loops.
immediately to the user application.
It should be noted that depending on the underlying transport
-mechanism being used, it is extremly possible that during
-normal operations that retry conditions are very likely to
-happen. These are completely out of RMr's control, and there
-is nothing that RMr can do to avoid or midigate these other
-than by allowing RMr to retry the send operation, and even
-then it is possible (e.g. during connection reattempts), that
-a single retry loop is not enough to guarentee a successful
-send.
+mechanism being used, it is extremely likely that retry
+conditions will happen during normal operations. These are
+completely out of RMR's control, and there is nothing that
+RMR can do to avoid or mitigate these other than by allowing
+RMR to retry the send operation, and even then it is possible
+(e.g., during connection reattempts), that a single retry
+loop is not enough to guarantee a successful send.
RETURN VALUE
--------------------------------------------------------------------------------------------
int retries_left = 5; // max retries on dev not available
static rmr_mbuf_t* mbuf = NULL; // response msg
msg_t* pm; // private message (payload)
- m// get a send buffer and reference the payload
+ // get a send buffer and reference the payload
mbuf = rmr_alloc_msg( mr, RMR_MAX_RCV_BYTES );
pm = (msg_t*) mbuf->payload;
- p// generate an xaction ID and fill in payload with data and msg type
+ // generate an xaction ID and fill in payload with data and msg type
rmr_bytes2xact( mbuf, xid, RMR_MAX_XID );
snprintf( pm->req, sizeof( pm->req ), "{ \\"req\\": \\"num users\\"}" );
mbuf->mtype = MT_USR_RESP;
-
- msg = rmr_mt_call( mr, msg, my_id, 100 ); e :// wait up to 100ms
+ msg = rmr_mt_call( mr, msg, my_id, 100 ); // wait up to 100ms
if( ! msg ) { // probably a timeout and no msg received
return NULL; // let errno trickle up
- }
+ }
if( mbuf->state != RMR_OK ) {
while( retries_left-- > 0 && // loop as long as eagain
- mbuf->state == RMR_ERR_RETRY &&
- (msg = rmr_mt_call( mr, msg )) != NULL &&
+ mbuf->state == RMR_ERR_RETRY &&
+ (msg = rmr_mt_call( mr, msg )) != NULL &&
mbuf->state != RMR_OK ) {
usleep( retry_delay );
}
-
+
if( mbuf == NULL || mbuf->state != RMR_OK ) {
rmr_free_msg( mbuf ); // safe if nil
return NULL;
allocate one.
The *old_msg* parameter allows the user to pass a previously
-generated RMr message back to RMr for reuse. Optionally, the
+generated RMR message back to RMR for reuse. Optionally, the
user application may pass a nil pointer if no reusable
message is available. When a timeout occurs, and old_msg was
not nil, the state will be returned by returning a pointer to
the old message with the state set.
It is possible to use the *rmr_rcv_msg()* function instead of
-this function. Doing so might be advantagous if the user
+this function. Doing so might be advantageous if the user
programme does not always start the multi-threaded mode and
the use of *rmr_rcv_msg()* would make the flow of the code
-more simple. The advantags of using this function are the
+more simple. The advantages of using this function are the
ability to set a timeout without using epoll, and a small
performance gain (if multi-threaded mode is enabled, and the
*rmr_rcv_msg()* function is used, it simply invokes this
mode with the same "pass through" overhead to using this
function directly.
-NOTE: Currently the multi-threaded functions are supported
-only when the NNG transport mechanism is being used. It will
-not be possible to link a programme using the nanomsg version
-of the library when references to this function are present.
-
RETURN VALUE
--------------------------------------------------------------------------------------------
ERRORS
--------------------------------------------------------------------------------------------
-The *state* field in the message buffer will indicate either
-RMR_OK when the message receive process was successful and
-the message can be used by the caller. Depending on the
+The *state* field in the message buffer will indicate RMR_OK
+when the message receive process was successful and the
+message can be used by the caller. Depending on the
underlying transport mechanism, one of the following RMR
error stats may be returned:
message buffer with the payload which is large enough to hold
*new_len* bytes. If the *clone* option is true, this will be
a pointer to the newly cloned message buffer; the original
-message buffer pointer may still be used to referenced that
+message buffer pointer may still be used to reference that
message. It is the calling application's responsibility to
free the memory associateed with both messages using the
rmr_free_msg() function.
if( msg == NULL ) {
fprintf( stderr, "[ERR] realloc returned a nil pointer: %s\\n", strerror( errno ) );
} else {
- } e// populate and send ack message
- }}
+ // populate and send ack message
+ }
}
Retries
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-The send operations in RMr will retry *soft* send failures
+The send operations in RMR will retry *soft* send failures
until one of three conditions occurs:
2.
- The underlying transport reports a * hard * failure
+ The underlying transport reports a *hard* failure
3.
The maximum number of retry loops has been attempted
-A retry loop consists of approximately 1000 send attemps **
-without** any intervening calls to * sleep() * or * usleep().
-* The number of retry loops defaults to 1, thus a maximum of
+A retry loop consists of approximately 1000 send attempts
+**without** any intervening calls to *sleep()* or *usleep().*
+The number of retry loops defaults to 1, thus a maximum of
1000 send attempts is performed before returning to the user
application. This value can be set at any point after RMr
-initialisation using the * rmr_set_stimeout() * function
+initialisation using the *rmr_set_stimeout()* function
allowing the user application to completely disable retires
(set to 0), or to increase the number of retry loops.
immediately to the user application.
It should be noted that depending on the underlying transport
-mechanism being used, it is extremly possible that during
-normal operations that retry conditions are very likely to
-happen. These are completely out of RMr's control, and there
-is nothing that RMr can do to avoid or midigate these other
-than by allowing RMr to retry the send operation, and even
-then it is possible (e.g. during connection reattempts), that
-a single retry loop is not enough to guarentee a successful
-send.
+mechanism being used, it is extremely likely that retry
+conditions will happen during normal operations. These are
+completely out of RMR's control, and there is nothing that
+RMR can do to avoid or mitigate these other than by allowing
+RMR to retry the send operation, and even then it is possible
+(e.g., during connection reattempts), that a single retry
+loop is not enough to guarantee a successful send.
PAYLOAD SIZE
--------------------------------------------------------------------------------------------
case of a received message, it is possible that the response
needs to be larger than the payload associated with the
inbound message. In order to use the return to sender
-function, the source infomration in the orignal message must
+function, the source information in the original message must
be present in the response; information which cannot be added
to a message buffer allocated through the standard RMR
allocation function. To allocate a buffer with a larger
state and should be RMR_OK.
If the state in the returned buffer is anything other than
-UT_OK, the user application may need to attempt a
+RMR_OK, the user application may need to attempt a
retransmission of the message, or take other action depending
on the setting of errno as described below.
Retries
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-The send operations in RMr will retry *soft* send failures
+The send operations in RMR will retry *soft* send failures
until one of three conditions occurs:
2.
- The underlying transport reports a * hard * failure
+ The underlying transport reports a *hard* failure
3.
The maximum number of retry loops has been attempted
-A retry loop consists of approximately 1000 send attemps **
-without** any intervening calls to * sleep() * or * usleep().
-* The number of retry loops defaults to 1, thus a maximum of
+A retry loop consists of approximately 1000 send attempts
+**without** any intervening calls to *sleep()* or *usleep().*
+The number of retry loops defaults to 1, thus a maximum of
1000 send attempts is performed before returning to the user
application. This value can be set at any point after RMr
-initialisation using the * rmr_set_stimeout() * function
+initialisation using the *rmr_set_stimeout()* function
allowing the user application to completely disable retires
(set to 0), or to increase the number of retry loops.
immediately to the user application.
It should be noted that depending on the underlying transport
-mechanism being used, it is extremly possible that during
-normal operations that retry conditions are very likely to
-happen. These are completely out of RMr's control, and there
-is nothing that RMr can do to avoid or midigate these other
-than by allowing RMr to retry the send operation, and even
-then it is possible (e.g. during connection reattempts), that
-a single retry loop is not enough to guarentee a successful
-send.
+mechanism being used, it is extremely likely that retry
+conditions will happen during normal operations. These are
+completely out of RMR's control, and there is nothing that
+RMR can do to avoid or mitigate these other than by allowing
+RMR to retry the send operation, and even then it is possible
+(e.g., during connection reattempts), that a single retry
+loop is not enough to guarantee a successful send.
RETURN VALUE
--------------------------------------------------------------------------------------------
static rmr_mbuf_t* send_msg = NULL; // message to send; reused on each call
msg_t* send_pm; // payload for send
msg_t* pm; // our message format in the received payload
- mif( send_msg == NULL ) {
- send_msg = rmr_alloc_msg( mr, MAX_SIZE ); r// new buffer to send
- }
- // reference payload and fill in message type
+ if( send_msg == NULL ) {
+ send_msg = rmr_alloc_msg( mr, MAX_SIZE ); // new buffer to send
+ }
+ // reference payload and fill in message type
pm = (msg_t*) send_msg->payload;
send_msg->mtype = MT_ANSWER;
msg->len = generate_data( pm ); // something that fills the payload in
msg = rmr_send_msg( mr, send_msg ); // ensure new pointer used after send
- mif( ! msg ) {
- m !return ERROR;
- m} else {
- m sif( msg->state != RMR_OK ) {
- m s m// check for RMR_ERR_RETRY, and resend if needed
- m s m// else return error
- m s}
- m}
- mreturn OK;
+ if( ! msg ) {
+ return ERROR;
+ } else {
+ if( msg->state != RMR_OK ) {
+ // check for RMR_ERR_RETRY, and resend if needed
+ // else return error
+ }
+ }
+ return OK;
The rmr_set_fack function enables *fast TCP acknowledgements*
if the underlying transport library supports it. This might
-be useful for applications which must send messages as a
+be useful for applications which must send messages at a
maximum rate.
RETURN VALUE
::
#define NO_FLAGS 0
- char* Oport = "43086"; // port for message router listen
- int rmax_size = 4096; // max message size for default allocations
- void* mr_context; // message router context
+ char* port = "43086"; // port for message router listen
+ int max_size = 4096; // max message size for default allocations
+ void* mr_context; // message router context
mr_context = rmr_init( port, max_size, NO_FLAGS );
if( mr_context != NULL ) {
rmr_set_stimeout( mr_context, 0 ); // turn off retries
NAME
--------------------------------------------------------------------------------------------
-rmr_set_trace
+rmr_set_vlevel
SYNOPSIS
--------------------------------------------------------------------------------------------
as it can grossly affect performance.
-generally RMR does not write messages to the standard error
+Generally RMR does not write messages to the standard error
device from *critical path* functions, therefore it is
usually not harmful to enable a verbosity level of either
-RMR_VL_CRIT, or RMR_VL_ERR.
+RMR_VL_CRIT or RMR_VL_ERR.
Messages written from the route table collection thread are
still governed by the value placed into the verbose level
DESCRIPTION
--------------------------------------------------------------------------------------------
-The rmr_trace_ref function return a pointer to the trace area
-in the message, and optionally populate the user programme
-supplied size integer with the trace area size, if *sizeptr*
-is not nil.
+The rmr_trace_ref function returns a pointer to the trace
+area in the message, and optionally populates the user
+programme supplied size integer with the trace area size, if
+*sizeptr* is not nil.
RETURN VALUE
--------------------------------------------------------------------------------------------
::
#include <rmr/rmr.h>
- rmr_mbuf_t* rmr_tralloc_msg( void* vctx, int size,
+ rmr_mbuf_t* rmr_tralloc_msg( void* vctx, int size,
int trace_size, unsigned const char *tr_data );
DESCRIPTION
--------------------------------------------------------------------------------------------
-The rmr_alloc_msg function is used to allocate a buffer which
-the user programme can write into and then send through the a
-library. The buffer is allocated such that sending it
+The rmr_tralloc_msg function is used to allocate a buffer
+which the user programme can write into and then send through
+the library. The buffer is allocated such that sending it
requires no additional copying from the buffer as it passes
through the underlying transport mechanism.
The *size* parameter is used to set the payload length in the
-message and If it is 0, then the default size supplied on the
+message. If it is 0, then the default size supplied on the
*rmr_init* call will be used. In addition to allocating the
payload, a space in the buffer is reserved for *trace* data
(tr_size bytes), and the bytes pointed to by *tr_data* are
the message into which the user may write a transaction
ID. The ID is optional with the exception of when the user
application uses the rmr_call function to send a message
- and wait for the reply; the underlying a processing
- expects that the matching reply message will also contain
- the same data in the *xaction* field.
+ and wait for the reply; the underlying processing expects
+ that the matching reply message will also contain the same
+ data in the *xaction* field.
RETURN VALUE
Like *rmr_wh_send_msg,* this function attempts to send the
message directly to a process at the other end of a wormhole
-which was created with *rmr_wh-open().* When sending message
-via wormholes, the normal RMr routing based on message type
+which was created with *rmr_wh_open().* When sending message
+via wormholes, the normal RMR routing based on message type
is ignored, and the caller may leave the message type
unspecified in the message buffer (unless it is needed by the
receiving process). The call_id parameter is a number in the
Retries
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-The send operations in RMr will retry *soft* send failures
+The send operations in RMR will retry *soft* send failures
until one of three conditions occurs:
2.
- The underlying transport reports a * hard * failure
+ The underlying transport reports a *hard* failure
3.
The maximum number of retry loops has been attempted
-A retry loop consists of approximately 1000 send attemps **
-without** any intervening calls to * sleep() * or * usleep().
-* The number of retry loops defaults to 1, thus a maximum of
+A retry loop consists of approximately 1000 send attempts
+**without** any intervening calls to *sleep()* or *usleep().*
+The number of retry loops defaults to 1, thus a maximum of
1000 send attempts is performed before returning to the user
application. This value can be set at any point after RMr
-initialisation using the * rmr_set_stimeout() * function
+initialisation using the *rmr_set_stimeout()* function
allowing the user application to completely disable retires
(set to 0), or to increase the number of retry loops.
immediately to the user application.
It should be noted that depending on the underlying transport
-mechanism being used, it is extremly possible that during
-normal operations that retry conditions are very likely to
-happen. These are completely out of RMr's control, and there
-is nothing that RMr can do to avoid or midigate these other
-than by allowing RMr to retry the send operation, and even
-then it is possible (e.g. during connection reattempts), that
-a single retry loop is not enough to guarentee a successful
-send.
+mechanism being used, it is extremely likely that retry
+conditions will happen during normal operations. These are
+completely out of RMR's control, and there is nothing that
+RMR can do to avoid or mitigate these other than by allowing
+RMR to retry the send operation, and even then it is possible
+(e.g., during connection reattempts), that a single retry
+loop is not enough to guarantee a successful send.
RETURN VALUE
--------------------------------------------------------------------------------------------
::
- #include <rmr/rmr.h> .// system headers omitted for clarity
+ #include <rmr/rmr.h> // system headers omitted for clarity
int main() {
rmr_whid_t whid = -1; // wormhole id for sending
void* mrc; //msg router context
int count = 0;
mrc = rmr_init( "43086", RMR_MAX_RCV_BYTES, RMRFL_NONE );
if( mrc == NULL ) {
- fprintf( stderr, "[FAIL] unable to initialise RMr environment\\n" );
+ fprintf( stderr, "[FAIL] unable to initialise RMR environment\\n" );
exit( 1 );
}
- while( ! rmr_ready( mrc ) ) { e i// wait for routing table info
+ while( ! rmr_ready( mrc ) ) { // wait for routing table info
sleep( 1 );
}
sbuf = rmr_alloc_msg( mrc, 2048 );
while( 1 ) {
if( whid < 0 ) {
whid = rmr_wh_open( mrc, "localhost:6123" ); // open fails if endpoint refuses conn
- w if( RMR_WH_CONNECTED( wh ) ) {
+ if( RMR_WH_CONNECTED( wh ) ) {
snprintf( sbuf->payload, 1024, "periodic update from sender: %d", count++ );
sbuf->len = strlen( sbuf->payload );
- sbuf = rmr_wh_call( mrc, whid, sbuf, 1000 ); f s// expect a response in 1s or less
+ sbuf = rmr_wh_call( mrc, whid, sbuf, 1000 ); // expect a response in 1s or less
if( sbuf != NULL && sbuf->state = RMR_OK ) {
- sprintf( stderr, "response: %s\\n", sbuf->payload ); x// assume they sent a string
+ sprintf( stderr, "response: %s\\n", sbuf->payload ); // assume they sent a string
} else {
sprintf( stderr, "response not received, or send error\\n" );
}
NAME
--------------------------------------------------------------------------------------------
-rmr_wh_open
+rmr_wh_close
SYNOPSIS
--------------------------------------------------------------------------------------------
with this ID will fail.
The underlying TCP connection to the remote endpoint is
-**not** closed as this session may be reqruired for
-regularlly routed messages (messages routed based on message
-type). There is no way to force a TCP session to be closed at
-this point in time.
+**not** closed as this session may be required for regularly
+routed messages (messages routed based on message type).
+There is no way to force a TCP session to be closed at this
+point in time.
SEE ALSO
--------------------------------------------------------------------------------------------
EACCESS
- The user applicarion does not have the ability to
+ The user application does not have the ability to
establish a wormhole to the indicated target (or maybe any
target).
rmr_whid_t wh;
rmc = rmr_init( "43086", 4096, 0 ); // init context
wh = rmr_wh_open( rmc, "localhost:6123" );
- if( !RMR_WH_CONNECTED( wh ) ) {
- f fprintf( stderr, "unable to connect wormhole: %s\\n",
+ if( !RMR_WH_CONNECTED( wh ) ) {
+ fprintf( stderr, "unable to connect wormhole: %s\\n",
strerror( errno ) );
}
wormhole ID provided (id). Unlike *rmr_send_msg,* this
function attempts to send the message directly to a process
at the other end of a wormhole which was created with
-*rmr_wh-open().* When sending message via wormholes, the
-normal RMr routing based on message type is ignored, and the
+*rmr_wh_open().* When sending message via wormholes, the
+normal RMR routing based on message type is ignored, and the
caller may leave the message type unspecified in the message
buffer (unless it is needed by the receiving process).
The message buffer (msg) used to send is the same format as
-used for regular RMr send and reply to sender operations,
+used for regular RMR send and reply to sender operations,
thus any buffer allocated by these means, or calls to
*rmr_rcv_msg()* can be passed to this function.
Retries
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-The send operations in RMr will retry *soft* send failures
+The send operations in RMR will retry *soft* send failures
until one of three conditions occurs:
2.
- The underlying transport reports a * hard * failure
+ The underlying transport reports a *hard* failure
3.
The maximum number of retry loops has been attempted
-A retry loop consists of approximately 1000 send attemps **
-without** any intervening calls to * sleep() * or * usleep().
-* The number of retry loops defaults to 1, thus a maximum of
+A retry loop consists of approximately 1000 send attempts
+**without** any intervening calls to *sleep()* or *usleep().*
+The number of retry loops defaults to 1, thus a maximum of
1000 send attempts is performed before returning to the user
application. This value can be set at any point after RMr
-initialisation using the * rmr_set_stimeout() * function
+initialisation using the *rmr_set_stimeout()* function
allowing the user application to completely disable retires
(set to 0), or to increase the number of retry loops.
immediately to the user application.
It should be noted that depending on the underlying transport
-mechanism being used, it is extremly possible that during
-normal operations that retry conditions are very likely to
-happen. These are completely out of RMr's control, and there
-is nothing that RMr can do to avoid or midigate these other
-than by allowing RMr to retry the send operation, and even
-then it is possible (e.g. during connection reattempts), that
-a single retry loop is not enough to guarentee a successful
-send.
+mechanism being used, it is extremely likely that retry
+conditions will happen during normal operations. These are
+completely out of RMR's control, and there is nothing that
+RMR can do to avoid or mitigate these other than by allowing
+RMR to retry the send operation, and even then it is possible
+(e.g., during connection reattempts), that a single retry
+loop is not enough to guarantee a successful send.
RETURN VALUE
--------------------------------------------------------------------------------------------
::
- #include <rmr/rmr.h> .// system headers omitted for clarity
+ #include <rmr/rmr.h> // system headers omitted for clarity
int main() {
rmr_whid_t whid = -1; // wormhole id for sending
void* mrc; //msg router context
int count = 0;
mrc = rmr_init( "43086", RMR_MAX_RCV_BYTES, RMRFL_NONE );
if( mrc == NULL ) {
- fprintf( stderr, "[FAIL] unable to initialise RMr environment\\n" );
+ fprintf( stderr, "[FAIL] unable to initialise RMR environment\\n" );
exit( 1 );
}
- while( ! rmr_ready( mrc ) ) { e i// wait for routing table info
+ while( ! rmr_ready( mrc ) ) { // wait for routing table info
sleep( 1 );
}
sbuf = rmr_alloc_msg( mrc, 2048 );
while( 1 ) {
if( whid < 0 ) {
whid = rmr_wh_open( mrc, "localhost:6123" ); // open fails if endpoint refuses conn
- w if( RMR_WH_CONNECTED( wh ) ) {
+ if( RMR_WH_CONNECTED( wh ) ) {
snprintf( sbuf->payload, 1024, "periodic update from sender: %d", count++ );
sbuf->len = strlen( sbuf->payload );
sbuf = rmr_wh_send_msg( mrc, whid, sbuf );
- }
- }
- sleep( 5 );
+ }
+ }
+ sleep( 5 );
}
}
Code Review / ric-plt / lib / rmr.git / blobdiff