touch(1) - change file timestamps
-a     change only the access time
-c, --no-create
       do not create any files
-d, --date=STRING
       parse STRING and use it instead of current time

-f     (ignored)
-h, --no-dereference
       affect each symbolic link instead of any referenced file (useful only on systems that  can  change
       the timestamps of a symlink)
-m     change only the modification time
-r, --reference=FILE
       use this file's times instead of current time
       use [[CC]YY]MMDDhhmm[.ss] instead of current time
       change  the  specified  time:  WORD  is  access, atime, or use: equivalent to -a WORD is modify or
       mtime: equivalent to -m
--help display this help and exit
       output version information and exit