File Dates – How to Copy Creation and Modification Dates of a File to Another File

If you don't have permission, then you can't copy the file.

The only ways around that are by elevating your permissions, for example by becoming root or the other user. You could try 'scp':

scp other_user@localhost:file .

or copy the file as root (but then be aware that the destination file is owned by root).

A Posix file system node typically has three time attributes:

• atime (access time) -- when was the file last read
• mtime (modification time) -- when was it last written to.
• ctime (change time) -- when was its inode (metadata) changed.

The ctime attribute is frequently misunderstood as creation time, and sometimes it is, which tends to confuse people.

POSIX shells have no standard way of extracting these three attributes, and you will depend on the ls command. ls -l $file by default shows modification time.

• ls -lc $file shows ctime
• ls -lu $file shows atime

It is recommended to use ls --time-style=full-iso or another iso format for consistent output, if you are on a GNU/linux system.

In Perl and other scripting languages, it's easier to stat() a file and access its attributes. Perl even has the -M, -A, and -C operators that return mtime, atime, and ctime for a file system object. Note the time offset, though. Perl tends to report times relative to the process start time.