## Chapter 19 – NextZXOS and alternatives ### Guide to NextZXOS Until now, we have been talking about *NextBASIC*, the programming language with which you "talk" to your ZX Spectrum Next and get it to do things. Underneath *NextBASIC* however, lurks another program, one that allows your computer to communicate with the hardware devices connected to it and the world at large. It manages your computer's memory, makes sure your data is safe and accurate, that your programs behave as intended by their programmers and performs important "housekeeping" on your storage devices. This program is called an *operating system* and in the ZX Spectrum Next's case it is called *NextZXOS*. *NextZXOS*, written by Garry Lancaster, is the direct successor to his *+3e/IDEDOS*, which in turn comes directly from the first proper Sinclair ZX Spectrum *operating system* called *+3DOS* which first appeared on the ZX Spectrum +3. ### NextZXOS main features *NextZXOS* extends *+3DOS*, *+3e* and *IDEDOS* and features the following: - *FAT16* and *FAT32* support for industry-standard compatibility with mass storage devices while retaining *IDEDOS/+3DOS* compatibility for a full range of storage choices - Long File Name (LFN)[^p157-1] support - Proper subfolders/subdirectories - Memory Management facilities - Virtual (container) *file systems* in *disk* and *tape images*[^p157-2] - Installable device drivers - Menu-driven file manager with extensible filetype associations/launchers - *esxDOS* emulation layer for interoperability across ZX Spectrum compatible machines and extended *dot command* support - Automatic execution of software on boot - Command-line interface - *Streaming* support - Virtual memory support (*swap partitions*) - Timekeeping facilities - Availability of disk and file management even on legacy (via *dot commands*), 48K modes - Increased compatibility with previous models of ZX family of computers[^p157-3] - Support for a variety of *snapshot* formats - Multi-lingual and multi-font capabilities - Extended windowing facilities - Increased speed of operation compared to the previous versions - Proper CP/M[^p157-4] 3 compatibility Unlike other operating systems, *NextZXOS* tightly integrates with the in-built programming language *NextBASIC*, to the point that it can be mistaken as being part of it. In reality however, *NextZXOS* provides two rich *APIs* (one being the native *NextZXOS API* and the other [^p157-1]: Long File Name support means that a filename under *NextZXOS* can be up to 255 characters long as opposed to the earlier 11 (8 for filenames +3 for extension/filetype) character limit. LFN capability is not reserved for files. Folders can also be up to 255 characters long. Longer file and folder names help with the organisation of your files as it is easier to use more descriptive names. [^p157-2]: A container file system / disk image is a bit-for-bit copy of the contents of a mass storage medium contained within a single file. For example what used to be an entire floppy disk can be represented by one file, which *NextZXOS* will access with traditional disk and file management commands once this is attached (mounted) by the operating system. [^p157-3]: *NextZXOS* is compatible –via emulators provided by Paul Farrow– with ZX80 and ZX81 while also being more compatible than its predecessor with Timex Sinclair as well as the 128K and 48K lines of ZX Spectrum machines. [^p157-4]: CP/M is an older operating system for personal computers with a vast library of software.