()()

Syntax

viOpenDefaultRM(out int sesn);

Description

Opens the default VISA Resource Manager, the Class Factory1 VISA Object that knows how to find and open VISA resources.  This function must be called before any other VISA functions can be invoked. The first call to this function initializes the VISA system, including the Default Resource Manager resource, and also returns a session to that resource. Subsequent calls to this function return unique sessions to the same Default Resource Manager resource.

Parameters

Name	Dir	Type	Description
sesn	OUT	int	Unique logical identifier to a Default Resource Manager session.

Return Values

Completion Code	Description
VI_SUCCESS	Session to the Default Resource Manager resource created successfully.
Error Codes	Description
VI_ERROR_ALLOC	Insufficient system resources to create a session to the Default Resource Manager resource.
VI_ERROR_INV_SETUP	Some implementation-specific configuration file is corrupt or does not exist.
VI_ERROR_SYSTEM_ERROR	The VISA system failed to initialize.

C# Example

public int OpenRM()
{
	int resourceManager, viError;
	viError = visa32.viOpenDefaultRM(out resourceManager);
	if (viError < visa32.VI_SUCCESS)
		throw new ApplicationException(
					"Failed to open Resource Manager");
	return resourceManager;
}

VB .NET Example

Public Function OpenRM() As Integer
    Dim resourceManager As Integer = 0, viError As Integer
    viError = visa32.viOpenDefaultRM(resourceManager)
    If viError < visa32.VI_SUCCESS Then
        Throw New ApplicationException("Failed to open Resource Manager")
    End If
    Return resourceManager
End Function

1See the excellent book Design Patterns, Gamma et al, for more information about the Class Factory pattern and other commonly used patterns in software systems.