Boot time viewing gadget

In the past, my company had flexible working hours for developers. They could open their fingerprints between 8 a.m. and 9 a.m. in the morning, and then get off work between 5:30 p.m. and 6:30 p.m. If you opened it at 8 a.m., Then you can get off work at 5:30 pm, but it is impossible for us to remember when we punched in the morning after get off work every day. Therefore, if there is such a tool that can roughly know when we punched in, then we don’t have to go to such trouble. , then I thought about it, why not use the computer boot time as a reference, because we office workers basically turn on the computer as soon as we come to the company in the morning, so the computer boot time is basically the same as the clock in time, unless you know how to use the computer after working or hate it Turn on the computer late.
Let’s talk about it. The principle of this simple gadget is actually very simple. It is to read the system log of the operating system and determine the earliest boot time of the day. Of course, if you worked overtime until one or two o’clock last night, then it may not be possible. Accurate, but then I thought about it, can I make a judgment on the logic of the program? If our company starts work at 8 o'clock, then if we find that the system log has system logs from 1 o'clock to 7 o'clock, can we just check the system log from 7 o'clock to 7 o'clock? Log at 9 o'clock. Later, I thought about whether I could just select the boot time. If I found that there are multiple boot times, then list them and let the user make their own judgment. That would be perfect.

Finally, we found that when reading the log, we read it backwards, that is, reading the beginning of today, so the performance is much faster.