Add Print DateTime Represented By Unix Timestamp as a Unix TIL

README.md

@@ -10,7 +10,7 @@ pairing with smart people at Hashrocket.
 
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-_1406 TILs and counting..._
+_1407 TILs and counting..._
 
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@@ -1397,6 +1397,7 @@ _1406 TILs and counting..._
 - [Partial String Matching In Bash Scripts](unix/partial-string-matching-in-bash-scripts.md)
 - [PID Of The Current Shell](unix/pid-of-the-current-shell.md)
 - [Print A Range Of Lines For A File With Bat](unix/print-a-range-of-lines-for-a-file-with-bat.md)
+- [Print DateTime Represented By Unix Timestamp](unix/print-datetime-represented-by-unix-timestamp.md)
 - [Print Milliseconds In Human-Readable Format](unix/print-milliseconds-in-human-readable-format.md)
 - [Print Out Files In Reverse](unix/print-out-files-in-reverse.md)
 - [Print The Current Date In Human-Readable Format](unix/print-the-current-date-in-human-readable-format.md)

unix/print-datetime-represented-by-unix-timestamp.md

@@ -0,0 +1,16 @@
+# Print DateTime Represented By Unix Timestamp
+
+A lot of tools and systems use a Unix timestamp to represent a point in time.
+It is the number of seconds since the Unix epoch (Jan 1, 1970). However, just
+looking at a timestamp like `1623867544` doesn't tell a human much. I can't
+mentally translate that to the date and time that it is representing.
+
+The `date` utility can help. Give it the `-r` flag with the timestamp value (in
+seconds) and it will display the date and time in a human-readable format.
+
+```bash
+❯ date -r '1623867544'
+Wed Jun 16 13:19:04 CDT 2021
+```
+
+See `man date` for more details.