Question

I am trying to find a file that are 0 days old. Below are the steps I performed to test this

$ ls
$ ls -ltr
total 0
$ touch tmp.txt
$ ls -ltr
total 0
-rw-r-----   1 tstUser tstUser           0 Feb 28 20:02 tmp.txt
$ find * -mtime 0
$
$ find * -mtime -1
tmp.txt
$

Why is ‘-mtime 0’ not getting me the file?

What is the exact difference between ‘-mtime 0’ and ‘-mtime -1’?

Im sure there must be other ways to find files that are 0 days old in unix, but im curious in understanding how this ‘-mtime’ actually works.

Answer 1

   -mtime n
          File's data was last modified n*24 hours ago.  See the  comments
          for -atime to understand how rounding affects the interpretation
          of file modification times.

So, -mtime 0 would be equal to: “File’s data was last modified 0 hours ago.
While -mtime 1 would be: “File’s data was last modified 24 hours ago”

Edit:

   Numeric arguments can be specified as

   +n     for greater than n,

   -n     for less than n,

   n      for exactly n.

So I guess -1 would be modified within the last 24 hours, while 1 would be exactly one day.