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EvmEventPost(3)
NAME
  EvmEventPost, EvmEventPostVa - Posts an event

SYNOPSIS
  #include <evm/evm.h>

  EvmStatus_t EvmEventPost(
	  EvmConnection_t connection,
	  const EvmEvent_t event );

  EvmStatus_t EvmEventPostVa(
	  EvmConnection_t connection,
	  const EvmEvent_t event,
	  [EvmItemId_t item_id,
	  const EvmItemValue_t item_id]...,
	  EvmITEM_NONE );

OPERANDS
  connection
      The connection through which events are posted. See EvmConnCreate(3).

  event
      The event that is to be posted to the specified connection. See
      EvmEventCreate(3).

  item_id
      The identifier for the event data item to be set. See EvmItemSet(3) for
      possible values for this operand, and the data contained by the data
      item.

  item_value
      The value to be stored in the associated item indicated by item_id.

DESCRIPTION
  An EVM client program uses the routines described on this page to pass
  events to the EVM daemon, for distribution to subscribers.

  EvmEventPost() posts an event that has already been created with
  EvmEventCreate() or EvmEventCreateVa().

  EvmEventPostVa() allows you to create, post and destroy an event in a
  single call. It first creates a new event, adding to it any data items
  supplied in the call. If the event operand is not NULL, the contents of the
  supplied event are then merged into the new event, and the new event is
  posted. The new event is destroyed before the routine returns, and the
  supplied event (if any) is unchanged. See EvmItemSetVa(3) for details of
  the item_ids and item_values that may be passed as operands to this
  routine.

  If you pass NULL as the connection operand to either of these routines the
  event is posted to the local daemon, using a temporary connection, which is
  destroyed before the routine returns.	 Because of the overhead associated
  with creating and destroying an EVM connection, you should pass NULL only
  if your program rarely posts events.

  If either routine is unable to pass the event to the daemon, the error is
  reported immediately through the return code. If the event is passed to the
  daemon, the type of response depends on the response mode specified when
  the connection was created.

NOTES
   1.  These routines do not destroy the event passed as the event operand.
       You must explicitly call EvmEventDestroy() to destroy the event and
       free its memory once it is no longer needed.

   2.  You should avoid posting a large number of events in rapid succession,
       since this may cause the connection's send buffer to fill, and the
       posting process to block until the EVM daemon has relieved some or all
       of the data. Although this is a normal part of process
       synchronization, some high-performance processes may prefer to block
       as infrequently as possible.  EvmConnControl() can be used to increase
       the size of the send buffer.  See EvmConnControl(3) for more
       information.

   3.  If you use extended item_ids to supply names and values of variable
       items to EvmEventPostVa(), be sure to supply the correct number of
       operands for each. A variable name and value is required for all such
       items, and some variable types require an additional argument. See
       EvmItemSetVa(3) for more information.

RESTRICTIONS
  None

RETURN VALUES
  EvmERROR_NONE
      The operation was completed without error.

  EvmERROR_EVENT_REJECTED
      The EVM daemon rejected the event. The most likely reasons for this to
      happen are that no template has been registered for the event, or that
      the caller is not authorized to post the event. See evmtemplate(4) and
      evm.auth(4) for more information.

  EvmERROR_INVALID_ARGUMENT
      One of the arguments to the function was invalid.

  EvmERROR_INVALID_VALUE
      A value in a structure member is invalid.

  EvmERROR_NO_MEMORY
      An operation failed because an attempt to acquire heap memory failed.

  EvmERROR_QUEUED
      The connection's output buffer is full, and the event has been queued
      in heap space. Another attempt will be made to flush the queue when the
      next call is made to EvmEventPost(3), or when the caller invokes
      EvmConnFlush(3).	This error code is only returned for connections for
      which EvmConnControl(3) has been invoked with the request argument set
      to EvmCONN_POST_NONBLOCK_SET.

  EvmERROR_READ
      A read error occurred while reading from the EVM daemon connection. The
      connection is no longer usable, and the caller should invoke
      EvmConnDestroy() to destroy it.

  EvmERROR_WRITE
      A write error occurred while writing to the EVM daemon connection. The
      connection is no longer usable, and the caller should invoke
      EvmConnDestroy() to destroy it.

ERRORS
  None

LIBRARY
  EVM Support Library (libevm.so, libevm.a)

FILES
  None

SEE ALSO
  Routines: EvmConnControl(3), EvmConnCreate(3), EvmConnDestroy(3),
  EvmConnRegistrationGet(3), EvmEventCreate(3), EvmEventDestroy(3),
  EvmItemSetVa(3)

  Files: kevm(7)

  Event Management: EVM(5)

  Event Connection: EvmConnection(5)

  EVM Events: EvmEvent(5)

Index for Section 3

Alphabetical listing for E

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