tabix peek?

[xzhou82]

Hi! I wonder if it's possible to implement a "peek" mode for tabix query, such that one can quickly get the amount of data within a genomic interval from an input file. The amount of data can be number of lines, or something else (number of bytes?).

Of course I can run the current tabix query to retrieve the actual contents and then count the number of lines. But this will become slow when querying a big interval from a large file, so I wonder if a speedy "peek" query can be implemented. This will help a lot in my genome browser building project.

Best,