Is /proc/pid/maps a snapshot?

I’ve written a little tool to grep inside the adddress space of a proces with a start and end delimiter in ECMAScript regex syntax. I’m parsing /proc/pid/maps twice to determine the largest mapping first. So if I’ve opened this mapping description first and rewind it with a seek( 0 ) do I still get the same data, i.e. is this file a snapshot with unlimited repeatable readability ?