Looks pretty good, though your counter has a race condition in it....

Consider two people hitting this code at almost the same time. Since the code is being multitasked, it is possible that one script will zero out the counter right before the next one reads it... Something like:

A: read counter      Data: linux:700 windows:6
A: zero out counter  Data: --------------------
B: read counter      Data: linux:0   windows:0
A: write out counter Data: linux:701 windows:6
B: zero out counter  Data: --------------------
B: write counter     Data: linux:1   windows:0  <-- Doh!
[download]

See File Locking for a tutorial on using flock to avoid this.

-Blake