The *dot command* that handles attributes is **.chmod** and has a bit of a different syntax than **MOVE** as it accepts four attributes **r**, **h**, **s** and **a**, for read-only, hidden, system and archive. The first is in essence the same as **p** for **MOVE** while **h** doesn't exist on *NextZXOS* (setting the system attribute makes it also hidden by default) but it does exist as an attribute on *FAT drives*. Trying: ``` .chmod TBBLUE.FW -h ``` you will see that nothing has changed when doing **CAT EXP**. If you however take your SD Card to a PC, you will be able to see the file again there. ### The RAMdisk You may have been wondering what point there is in storing information in the RAMdisk (**m:**) as it will be lost once the ZX Spectrum Next is switched off. Well, perhaps its most obvious use is to store chunks of *NextBASIC* program (or routines) which can be merged (using **MERGE "m:filename"**) into a smaller program, in sequence. This makes it possible to write about 90K of *NextBASIC* code, and hold it in the machine, without going into the more complicated **BANK** commands. Another little less obvious use is to store temporary files there that won't be needed when your program finishes. Memory is the fastest medium on your ZX Spectrum Next and quick access to files may be beneficial. As we saw in *Chapter 17*, one of the more interesting uses of the *RAMdisk* is in animation, where a series of pictures can be defined by a slow *NextBASIC* program, stored in drive **m:**, then called back to the screen at high speed. Obviously **BANK** is still the preferred way to do it, but for quick jobs that use *Layer 0* it's a quick and easy method! ### Drive and Partition Management We've talked about physical devices and virtual devices; we've also talked about the automounting features of *NextZXOS* but we haven't truly explored how the system manages *storage devices* and assigns them to *drives*. *NextZXOS* provides us with four commands to help us list and manage disks and drives. The drive and partition management commands are: **CAT TAB** that lists the physical storage devices attached to the system and what partitions they contain; **CAT ASN** that lists all drive assignments to whichever partition or disk (basically listing what's mounted), **MOVE … IN** to assign any device/partition physical or virtual to a drive (mount) and **MOVE … OUT** to remove an assigned partition from a drive as well as **REMOUNT** that allows us to change system disks on the fly. *NextZXOS* also provides us with a way to create *virtual disks* of varying sizes in the form of two dot commands: **.mkdata** and **.mkswap** #### CAT TAB and CAT ASN **CAT TAB** lists the storage devices currently connected to your ZX Spectrum Next and their partitions. It's syntax is: **CAT** [#*n*] **TAB** where *#n* is an optional *stream* to redirect the output to (e.g. to a file). On a standard ZX Spectrum Next with a single SD Card reader, giving ``` CAT TAB ``` will return: ``` MMC unit 0 (1024M) MMC unit 5 (1024M) 5>1>NEXT 1024M FAT32 ``` which illustrates also a point we made early in the chapter. Each SD Reader is assigned two device numbers (**0,5** and **1,6** for first and second SD Readers respectively) according to what partitions it holds. If for example we had eight partitions, seven IDEDOS and one FAT32 then our display would have been: