Shell Programming and Scripting

Hey,

I am writing a script to delete log files that are older than one day (I'm going to run it weekly). Basically, it should work so that it only keeps the current day, but keeping the previous day as well isn't a dealbreaker.

I am running the following line on the files listed below:

Code:

find ./rpt*.log -mtime +1

Code:

-rw-r--r-- 1 user usergroup 19195074 Nov 15 23:53 rpt.1115.log
-rw-r--r-- 1 user usergroup 17083282 Nov 16 23:46 rpt.1116.log
-rw-r--r-- 1 user usergroup 9561236 Nov 17 23:59 rpt.1117.log
-rw-r--r-- 1 user usergroup 9252635 Nov 18 23:56 rpt.1118.log
-rw-r--r-- 1 user usergroup 16840981 Nov 19 23:58 rpt.1119.log
-rw-r--r-- 1 user usergroup 11956072 Nov 20 15:05 rpt.1120.log

Assuming that I run the script at 16:00 on Nov 20, I would expect that it would return each of the above files except for the 19th and 20th. However, here are the results:

Code:

./rpt.1115.log
./rpt.1116.log
./rpt.1117.log

Could someone explain to me the results here, and why it's not returning the file modified at 23:58 on 11/18 as well?

Thanks.

It's not returning the 11/28 file because find's calculation discards remainders. From the POSIX find manual:
If find runs at 11/20 16:00, that file's mtime, 11/18 23:58, is about 1.66 days old (40 hours old) . Truncating the 1.66 result to 1 does not satisfy the condition you've specified -mtime +1, for which a true result requires a value greater than or equal to 2.

Use ! -mtime -1.

Regards,
Alister