Hi Jacky,
The Ivi_RestrictAttrToInstances and Ivi_RestrictAttrToChannels are very similar. Multiple channels are a type of repeated capability instance. You could think of Ivi_RestrictAttrToChannels as a subset of Ivi_RestrictAttrToInstances. You can call Ivi_RestrictAttrToChannels only on attributes for which you have enabled the IVI_VAL_MULTI_CHANNEL flag. The Ivi_RestrictAttrToInstances function can be used on any repeated capability, such as channels on an oscilloscope, traces on a spectrum analyzer, or modulators on a RF signal generator.
