capture-filter for mdshdr fields

Hi All, I was using the display filter to filter my FC traffic. My display filter is something like this: -R mdshdr.srcidx==0x2f||mdshdr.dstidx==0x2f

As write and display filter don't work together, I wanted to know the equivalent of it in capture filter. How do I access mdshdr fiels in capture filter?

Thanks and Regards,

Aparna N