How to retrieve track pattern information of Metals in SKILL?

The track pattern will be loaded by default in virtuoso. I am writing a script to place metals over the selected instances based on the track pattern. Say I want to place a metal M1 of width 0.04 over the instance. i will check the M1 track spacing and place metal on the track to make it technology independent. But I am not able to figure out how to retrieve track pattern information through skill command. 

I tried following:

tech_id=ciGetTechFile( )

tech_id~>widthSpacingSnapPatternDefs~>??

But I was not able to find the what is the track pich for say M1, M2 etc.

I gone through .tf file from where track pattern is loaded, But I was not able to understand what to grep from it as I am not familiar with .tf files and track patterns.

So what is the best way and how to get track pattern information for metals.

Thanks,

Amshak