SUNWcsu
tmpfs is a memory based file system which uses kernel resources relating to the VM system and page cache as a file system.
mount attaches a tmpfs file system to the file system hierarchy at the pathname location mount_point, which must already exist. If mount_point has any contents prior to the mount operation, these remain hidden until the file system is once again unmounted. The attributes (mode, owner, and group) of the root of the tmpfs filesystem are inherited from the underlying mount_point, provided that those attributes are determinable. If not, the root’s attributes are set to their default values.
The special argument is usually specified as swap but is in fact disregarded and assumed to be the virtual memory resources within the system.
If the directory on which a file system is to be mounted is a symbolic link, the file system is mounted on the directory to which the symbolic link refers, rather than on top of the symbolic link itself.