C:\>del pid.txt

C:\>perl -lwe "print(':'.localtime((stat 'pid.txt')[10]))"
Use of uninitialized value in localtime at -e line 1.
:Thu Jan  1 01:00:00 1970

C:\>echo 8750 >pid.txt

C:\>perl -lwe "print(':'.localtime((stat 'pid.txt')[10]))"
:Tue Sep 20 11:30:49 2011