Unix timestamp/time window

Need some help figuring out how to check to see if a unix time stamp is within a specified time of day.

I am time stamping a sensor reading using unix format. I then want to check to see if the time stamp is within a set time window, say between 8:05 and 8:10 every day. Additionally I want to check if the current time is a specific day of the week, say a Saturday.

I have seen code examples that pull human readable strings and compare hours, minutes, and days of the week, but I have not seen a good way to do the above using unix format. Is there a way to use unix or do I need to poll the time in human readable strings?

-d, --date=STRING
    display time described by STRING, not 'now'
%a     locale's abbreviated weekday name (e.g., Sun)
%A     locale's full weekday name (e.g., Sunday)
%u     day of week (1..7); 1 is Monday
%H     hour (00..23)
%M     minute (00..59)
root@OpenWrt:~# date --date='@1456811582'
Tue Mar  1 05:53:02 UTC 2016
root@OpenWrt:~# date --date='@1456811582' +%A
root@OpenWrt:~# date --date='@1456811582' +%u
root@OpenWrt:~# date --date='@1456811582' +%H
root@OpenWrt:~# date --date='@1456811582' +%M


Can you point me to a web tutorial or reference that I can learn more?

Is there a syntax that works in an Arduino sketch?