The place you type it in is an app called Terminal. The command-line touch command works in Lion, but you need a little background on how to use it.įirstly, you need to type it in, it's not a utility that operates graphically in a window. (Of course, resetting the system date may not be a risk-free operation, you've been warned.) In summary, to be able to change the four timestamps independently, one may use (in this order for the last 3):

Unfortunately, it is not possible to specify the time explicitly here other than by changing the computer's time. This doesn't change the ownership of the file, but accesses the file's inode and records this as a time of last status change. Where username is the owner of the file (as reported by stat or ls -l). The first date listed is last access time ( atime), the second is last modification time ( mtime), the third is last status change ( ctime), the fourth is time of file creation (birth, Btime), see man lstat. These timestamps are not always updated independently from each other, but one can have some individual control with a bit of care and with use of touch, SetFile, and chown (or chmod). In Mac OS X there appears to be four different timestamps associated with a file.

Mac operating systems by date