touch(1) is used to change the timestamp on a file. You can change access timestamps and modification timestamps with this command. If the file specified does not exist, touch will create a zero length file with the name specified. To mark a file with the current system time, you would issue this command:
% ls -al file1 -rw-r--r-- 1 root root 9779 Feb 7 21:41 file1 % touch file1 % ls -al file1 -rw-r--r-- 1 root root 9779 Feb 8 09:17 file1 |
There are several options for touch, including options to specify which timestamp to modify, the time to use, and many more. The online manual page discusses these in detail.
mkdir(1) will create a new directory. You simply specify the directory to create when you run mkdir. This example creates the hejaz directory in the current directory:
% mkdir hejaz |
You can also specify a path, like this:
% mkdir /usr/local/hejaz |
The -p option will tell mkdir to make any parent directories. The above example will fail if /usr/local does not exist. The -p option will create /usr/local and /usr/local/hejaz:
% mkdir -p /usr/local/hejaz |