As part of writing a GTF trace formatter in Python I needed to covert a STCK value to a printable value. I could do it in C – but I did not find a Python equivalent.

from datetime import datetime
# Pass in a 8 bytes value
def stck(value):
    value = int.from_bytes(value)
    t = value/4096 #  remove the bottom 12 bits to get value in micro seconds
    tsm = (t /1000000 ) -  2208988800 # // number of seconds from Jan 1 1970 as float
    ts = datetime.fromtimestamp(tsm) # create the timestamp
    print("TS",tsm,ts.isoformat()) # format it

it produced

TS 1735804391.575975 2025-01-02T07:53:11.575975