Returns a ViSession handle that you use to identify the session in subsequent function calls.

This function creates a new session each time you invoke it. This is useful if you have multiple physical instances of the same type of instrument.

Avoid creating multiple concurrent sessions to the same physical instrument. Although you can create more than one IVI session for the same resource, it is best not to do so. A better approach is to use same session in multiple execution threads. You can use functions Ivi_LockSession and Ivi_UnlockSession to protect sections of code that require exclusive access to the resource.

Pass the ID of an attribute for this parameter.

The include file for a specific instrument driver defines constant names for all of the user-accessible attributes that apply to the driver. This includes attributes that the IVI engine defines, attributes that the instrument class defines, and attributes that are specific to the particular instrument. Each defined constant name begins with PREFIX_ATTR_, where PREFIX is the specific instrument prefix.

For each IVI engine attribute, the specific driver include file uses the same constant name that appears in ivi.h, except that the specific instrument prefix replaces the IVI prefix. For example, ivi.h defines IVI_ATTR_CACHE, and the Fluke 45 include file, fl45.h, defines the following constant name:

#define FL45_ATTR_CACHE  IVI_ATTR_CACHE

For each instrument class attribute, the specific driver include file uses the same constant name that appears in the instrument class include file, except that the specific instrument prefix replaces the class prefix. For example, the DMM class include file, ividmm.h, defines IVIDMM_ATTR_RANGE, and fl45.h defines the following constant name:

#define FL45_ATTR_RANGE  IVIDMM_ATTR_RANGE

For each specific instrument attribute, the specific driver include file defines a constant name and assigns a value that is an offset from IVI_SPECIFIC_PUBLIC_ATTR_BASE. For example, fl45.h defines the following constant name:

#define FL45_ATTR_HOLD_THRESHOLD \ (IVI_SPECIFIC_PUBLIC_ATTR_BASE + 3L)

For each attribute that is private to an instrument driver, the instrument driver source file defines a constant name and assigns a value that is an offset from IVI_SPECIFIC_PRIVATE_ATTR_BASE. For example, hp34401a.c defines the following constant name:

#define HP34401A_ATTR_TRIGGER_TYPE \ (IVI_SPECIFIC_PRIVATE_ATTR_BASE + 1L)

Specify the new values of the flags for the attribute. You express the flags as bits. You cannot modify the value of the IVI_VAL_MULTI_CHANNEL flag.

This function always sets all of the flags. If you want to change one flag, use Ivi_GetAttributeFlags to obtain the current values of all of the flags, modify the bit of the flag you want to change, and then call Ivi_SetAttributeFlags.

The code in the following example changes the IVI_VAL_NEVER_CACHE flag from 1 to 0.

IviAttrFlags oldFlags, newFlags;

Ivi_GetAttributeFlags (vi, attributeID, &oldFlags);newFlags = oldFlags & ~IVI_VAL_NEVER_CACHE;
Ivi_SetAttributeFlags (vi, attributeID, newFlags);

Valid Values: