Jump to content United States-English
HP.com Home Products and Services Support and Drivers Solutions How to Buy
» Contact HP
More options
HP.com home
HP-UX Reference > E

EvmConnControl(3)

HP-UX 11i Version 3: February 2007
» 

Technical documentation

» Feedback
Content starts here

 » Table of Contents

 » Index

NAME

EvmConnControl() — control information for an EVM connection

SYNOPSIS

#include <evm/evm.h> EvmStatus_t EvmConnControl( EvmConnection_t connection, EvmInt32_t request, void *arg);

Library

EVM Support Library (libevm.so).

Parameters

connection

The EVM connection to be controlled. See the EvmConnCreate(3) manpage.

request

The control action requested. See the DESCRIPTION section for the available requests.

arg

The value and use of arg depends on the request. See the DESCRIPTION section for the available meanings and the association to a request.

DESCRIPTION

The EvmConnControl() routine sets or gets control information for a connection.

The following list shows the available values for the request argument and the associated value of the arg argument.

request Argument

arg Argument Values

EvmCONN_RCV_SZ_GET

Gets the size of the connection's receive buffer. The arg argument is a pointer to an EvmInt32_t field to receive the size value.

EvmCONN_SND_SZ_GET

Gets the size of the connection's send buffer. The arg argument is a pointer to an EvmInt32_t field to receive the size value.

NOTE: EvmCONN_RCV_SZ_SET and EvmCONN_SND_SZ_SET, which set the receive and send buffer size, are not currently supported in HP-UX. Instead, use EvmConnFdGet() to get the socket descriptor of the connection, and use setsockopt() to change the buffer size of the socket.

EvmCONN_CHECKSUM_ENABLE

Enables checksum generation for posted events. This is the default state when a connection is established. The arg argument must be set to NULL.

EvmCONN_CHECKSUM_DISABLE

Disables checksum generation for posted events. This option is intended for use by high-performance applications that post events frequently using the local EVM daemon. The arg argument must be set to NULL.

EvmCONN_CHECKSUM_IS_ENABLED

Queries the connection to find out if checksum generation is enabled. The arg argument is a pointer to an EvmBoolean_t field to receive a boolean value.

EvmCONN_POST_ITEM_MASK_SET

Modifies the set of environmental data items that are inserted into events posted to the supplied connection. The arg argument is a EvmItemMask_t value containing a bitmap of item values to be inserted. Item enumeration values can be converted to bitmap form by using the EvmItemMask_() macro. For example,

EvmItemMask_(EvmITEM_TIMESTAMP) | EvmItemMask_(EvmITEM_USER_NAME)

EvmCONN_POST_ITEM_MASK_RESET

Restores the default set of environmental data items inserted automatically into events posted to the supplied connection. The arg argument must be set to NULL. This request clears the effects of any prior EvmCONN_POST_ITEM_MASK_SET requests.

EvmCONN_POST_NONBLOCK_SET

Controls the behavior of the calling process if an attempt to post an event would overflow the connection's send buffer. If this option is set to EvmFALSE (the default state when the connection is established), the process blocks as necessary to synchronize message transfer to the EVM daemon.

If it is set to EvmTRUE, EvmEventPost() returns EvmERROR_QUEUED if an event cannot be sent fully without blocking. In addition, the process must invoke EvmConnFlush() a short time later, to avoid unsent messages accumulating in memory. Further calls to EvmEventPost() also flush the queue. Refer to the EvmConnFlush(3) manpage for more details.

This option cannot be used for any connection type other than a posting connection with a response mode of EvmRESPONSE_IGNORE. This option is provided for critical high-performance processes which must post a large number of events in a very short time. This option is not suitable for general use.

The arg argument is an EvmBoolean_t value. A value of EvmFALSE allows the process to block if necessary. A value of EvmTRUE prevents blocking and enables message queuing.

RETURN VALUE

EvmERROR_NONE

The operation completed without error.

EvmERROR_INVALID_ARGUMENT

One of the arguments to the function is 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_RESOURCE

An unexpected error occurred while attempting to acquire or control a system resource.

EvmERROR_SIGNAL

The current operation was interrupted by receipt of a signal.

ERRORS

The value of errno is not set.

SEE ALSO

Event Management

EVM(5).

Event Connection

EvmConnection(5).

Printable version
Privacy statement Using this site means you accept its terms Feedback to webmaster
© 1983-2007 Hewlett-Packard Development Company, L.P.