datefmt is a simple C program that formats unix timestamps in text streams


Let’s say we have some logs that contain unix timestamps:

$ cat logs.txt

EVENTS  1638499687   blahblah log1
EVENTS  1638499717   blahblah log2

We can pipe this log into datefmt to convert these timestamps into human-readable dates:

$ <logs.txt datefmt

EVENTS  2021-12-02 18:48   blahblah log1
EVENTS  2021-12-02 18:48   blahblah log2

Of course you can customize the format as well:

$ <logs.txt datefmt "DATE:'%m-%d %R'"

EVENTS  DATE:'12-02 18:48'   blahblah log1
EVENTS  DATE:'12-02 18:48'   blahblah log2

It’s as simple as that! It comes with some heuristics so that it doesn’t parse timestamp outside of a reasonable range.


Tarballs are available here, please feel free to package this for your linux distribution of choice!

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