Uhrzeit vergleich

stat --help

stat -c%Y <file>

%X   Time of last access as seconds since Epoch
%Y   Time of last modification as seconds since Epoch
%Z   Time of last change as seconds since Epoch

...
       The field st_mtime is changed by file modifications, for example, by mknod(2), truncate(2), utime(2) and  write(2)  (of  more  than
       zero  bytes).   Moreover,  st_mtime of a directory is changed by the creation or deletion of files in that directory.  The st_mtime
       field is not changed for changes in owner, group, hard link count, or mode.

       The field st_ctime is changed by writing or by setting inode information (i.e., owner, group, link count, mode, etc.).
...