Editing Apple GS/OS (section)

==Features==

===Speed optimization===
The advantage of GS/OS over its predecessor, the ProDOS 16 operating system, is that it was written entirely in 16-bit code for the [[WDC 65C816|65816]] processor used in the II<small>GS</small>, rather than primarily in 8-bit [[MOS Technology 6502|6502]] machine code that does not take advantage of the II<small>GS</small>'s unique features. This in turn allows GS/OS to offer vast speed optimizations (loading time, disk access, screen updates) compared with the previous OS, and provided room to incorporate many features of other Apple operating systems, including [[Apple III]] [[Apple SOS]], the Macintosh [[Classic Mac OS#System Software 5|System 5]], as well as concepts and features that would later appear in future Macintosh System Software releases (e.g. proportional scrollbars, thermometer progress bars).

===New features and enhancements===
In addition to continued enhancements to the IIGS Finder and loadable fonts, GS/OS offered plug-in device drivers (modem, printer, etc.), a thermometer progress display, AppleShare support, File System Translators for accessing foreign file formats, disk caching and support for storage devices up to 4 Gigabytes.<ref>{{cite magazine |last=Arnett |first=Nick |date=1988-09-19  |title=Apple Unveils IIGS OS, Speedier Apple IIc Model |url=https://books.google.com/books?id=mDoEAAAAMBAJ&q=Apple+%22GS%2FOS%22&pg=PA39 |magazine=InfoWorld |volume=10|issue=38|publisher=IDG |page=39|issn=0199-6649|access-date=2016-08-03|quote=...Apple Computer last week introduced a new operating system for the Apple IIGS,.....The new GS/OS operating system for the Apple IIGS has an enhanced, more Mac-like Finder and speeds up booting......includes support for large storage devices, up to 4 gigabytes...GS/OS runs programs written for the earlier operating systems, Pro-Dos 16 and Pro-Dos 8...}}</ref> It also extends the ProDOS file system to provide for [[resource fork]]s on files similar to those used on the [[Mac (computer)|Apple Macintosh]], which allows for programs to be written in a more flexible way. The newly included Apple ''Advanced Disk Utilities'' and ''Apple IIGS Installer'' helped facilitate partitioning, formatting and installing software and drivers with visual ease. A command-line development environment called APW (Apple Programmer's Workshop) is available; much like the [[Macintosh Programmer's Workshop]].<ref>{{cite web |url=http://www.goldstarsoftware.com/applesite/Documentation/AppleIIgsProgrammersWorkshopC.PDF |title= Apple IIGS Programmer's Workshop - Version 1.0 (K2S002) |website=goldstarsoftware.com |access-date=2016-08-03 |quote=...APW C is intended for use with the Apple Programmer's Workshop...}}</ref><ref>{{cite web |url=http://www.byteworks.us/Byte_Works/Morgue.html |title=Morgue, Cortland Programmer's Workshop |website=byteworks.us |access-date=2016-08-03 |quote=...Apple decided to use a 16 bit version of ORCA/M as the standard development environment for the new machine, code named Cortland. On July 21, 1986, the last version of this environment that was still called Cortland Programmer’s Workshop was delivered to Apple for shipment to the developer community. Later versions were called Apple Programmer’s Workshop, or just APW... |archive-url=https://web.archive.org/web/20160819003213/http://www.byteworks.us/Byte_Works/Morgue.html |archive-date=2016-08-19 |url-status=dead}}</ref><ref>{{cite book |last=Westerfield |first=Mike |date=2013 |title=Building IPhone and IPad Electronic Projects: Real-World Arduino, Sensor, and Bluetooth Low Energy Apps in TechBASIC |chapter=About the Author|chapter-url=https://books.google.com/books?id=PaTEAAAAQBAJ&q=apple+%22ORCA%2FM%22&pg=PA317 |location=Beijing |publisher=O'Reilly Media|page=317 |isbn=978-1449363482|access-date=2016-08-03|quote=...Mike Westerfield...Two years later he finished ORCA/M, which went on to become Apple Programmer's Workshop, the Apple development environment for the Apple IIGS...}}</ref>

====File System Translators====
GS/OS includes a facility known as file system translators (FSTs) which allows it to support multiple on-disk file systems in a manner transparent to application programs and to the user,<ref name="GS/OS Reference">{{cite book |url=http://asimov.applefritter.com/unsorted/GS%20OS%20REFERENCE%20MANUAL.pdf |title=Apple IIGS GS/OS Reference |chapter=File System Translators |publisher=Apple |date=1990 |isbn=0-201-55020-2}}</ref> a feature not found in ProDOS or most other microcomputer operating systems at the time. While GS/OS natively uses the ProDOS file system (from which it must be booted), it also fully supports [[Hierarchical File System (Apple)|HFS]] used by [[Classic Mac OS|Mac OS]]. Other file system translators include those for the [[MS-DOS]] [[File Allocation Table|FAT file system]],<ref>{{cite web |url=https://wiki.preterhuman.net/GS/OS_MS-DOS_File_System_Translator_External_ERS_(1992) |title=GS/OS MS-DOS File System Translator External ERS |date=1992}}</ref> [[ISO 9660|High Sierra/ISO 9660]],<ref name="GS/OS Reference" />{{rp|page=299}} Apple DOS 3.3, and [[Apple Pascal]],<ref>{{cite book |url=https://www.applefritter.com/files/Pascal%20File%20System%20Translator%20External%20ERS.pdf |title=Pascal File System Translator External ERS Version 1.00 a03}}</ref> albeit read-only (full read/write support had been planned but was never completed).