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Hi-Tech / Mobile communication

The first Mac: Finder and file system

AppleInsider.ru - A blog about Apple 14.05.2018 at 19:00

All about Apple, iPhone, iPad, iPod, iMac, MacBook

The emergence of the myth of primitiveness and worthlessness Mac’ and blame its creators. They are too well done its work. The Mac system was more complicated and interesting of all the popular systems of the time, inside. Outwardly, everything was very simple, and just worked.

why user knowledge of the details of anatomy and physiology his personal assistant?

the worst kind of “expert” – pick up the top Amateurs. Those who actually owned, Mac appreciated. They are not deceived buying the simplicity of the interface, they found it very thoughtful, logical and convenient. “Today I saw what will be computers in five years”, they said.

But the “experts” were puzzled: who needs this plastic “talking” box, if it is absolutely impossible to understand? No command line, no text files containing scripts or configuration. Nothing at all! Well, not to look him “in the soul”!

to Open the casing? On it a sign: “do Not open, inside there is nothing interesting”. Someone still opened and really did not find anything interesting. Board, chips,...

I Wonder what they hoped to see there? A tiny alien who's confined to a microscopic control, with a bowl of dried alien worms?

Finder and the file system

the shell for the operating system of Macs with its first day and is still called Finder. “Whoever finds something”. On the border of the 80s and 90s, when disk storage became big, there was a joke: Finder that finds nothing (the Finder, which finds nothing), but in 1984, on a floppy disk with a capacity of 400 K to hide something was not easy.

This is a classic Mac app ovsky, written by Bruce horn and Steve Capps. Bruce is a genius and a perfectionist, “some lone nut”. To work with him on one task nobody could ever. But in the fall of 1983, when the last and final completion date of the project was only personal, Finder “stuck”.

Steve Capps was able to find common ground with Bruce. The problems were totally objective, but together they managed. In December 1983, the Finder was ready to come out into the light. That day the developers of Mac and staged a “day of Steve KAPS” – all came dressed as he dressed.

According to journalists, the main function of the Finder was the file system management Mac. Add to this definition only one word: “the Main apparent function...”. It is the realization of the metaphor of “desktop”, with documents and tools to work with them.

the File system of the first Mac a called MFS (Macintosh File System). It was not a hierarchy of directories, it was as flat as a bad joke, but for floppy disks with a capacity of 400 kilobytes, much of which was eaten by the system, it was necessary.

the Directory (for Mac ovsk – folders) to MFS really was an illusion. They were only visible in the Finder. Links to all the file system objects were stored in one invisible small file size.

the Hierarchical file system (HFS) was written much earlier, but at the time it was removed to the archive. Up to System 3.0 on Macs were only used MFS.

On a floppy disk system was originally two folders – System Folder and Empty Folder. In the Empty Folder, the user could “move” your documents and programs, as in a Desk drawer. Taking the necessary file and dragging it into an open or closed folder. Empty Folder can be renamed. And after the renaming the miracle happened: on the desktop immediately appeared a new empty folder called Empty Folder.

the File system is the very first Mac was called MFS (Macintosh File System), it was designed and optimized for unilateral 3.5-inch diskette with a capacity of 400 kilobytes, and laugh at her. She was “flat”. It was just “disk” (the disk), and files. A hierarchy of directories (folders, if Mac ovsk) was not.

When you delete a Empty Folder (for this it was necessary to drag into the “trash” (Trash) and to select the Special menu command “Empty Trash”. Empty ballot boxes destroyed all that was in it, users accustomed to the idea that it is unrecoverable. In fact, if the destruction of these files was not created with new, you can still improve, using a special tool – the truth, there he was, I think, in 1985.

Theoretically, to repair the file could be using a 16-hexadecimal editor, manually editing the contents of the invisible list of files and folders, but it was beyond good and evil: it was necessary to find a lost file, to correctly align its position on the disk in the designation, clear the “invisible file”, to correct the information of the “invisible file” and not to make mistakes – otherwise the system disk ceased to boot. Sent to the trash by mistake (or an experiment) that the file can be restore by using the command Put Back in the File menu. If “the trash hasn't endured”.

the names of the files intended for user, the file system is used to identify a unique ID (number). The names of the files and folders you can use absolutely any characters except the colon.

MFS can work with file names up to 255 characters, but the Finder has limited a flight of fancy user pathetic 63. In one version (3.0, I think), the length of the file name again restricted, this time 31 character. This restriction survived until 1998.

that is, if the “system font for displaying the file names in Finder” knew the Cyrillic, the folder could be called “Ya favorites. For 1984..1987”. And the documents in it, for example, “Tale of a runaway bull”.

the Contents of the active (selected) window if you wish, you can print another one. If there was a printer. Or send by Fax – if you had a modem and program Fax.

MFS can work with storage space up to 20 Megabytes or files with the 1400, at a time when the only accessible repository of information was one-sided floppies with a capacity of 400 K, these limits are theoretical.

the file system Objects

I in the previous section called user-visible file system objects in a word file. This, from the point of view of designers (in the best sense of the word) Mac and sin. In the system of Mac files was not only applications, documents, applications and system documents.

the Metaphor of the desktop is such a roleplay.

the Central element of this game was “documents”, double click on their icon they have opened, and if their application was not yet running, and opened it. (It seems that now it should “click” to call “clicking”, but this term is not very much).

the app could begin by double clicking on its icon – if the drive does not have documents of the required type or if it was more comfortable. Or if the application does not have any identification principle in (a game, 16-hex editor disk and the like).

In the role play was not involved, only system documents, with few exceptions double click on their icons did not lead to any action. They began to hide, and that's good. You had to install the driver, e.g., printer, PC DOS? But on a Mac the whole process was dragging a document, for example “Image Writer LQ” in the system folder. To remove the printer from working without removing it valuable system document (the driver), it was possible, by removing its icon from the System Folder.

Where documents and applications can know what icons to display them on the screen as someone to open it? Because no file extension in MFS was not. If you do not know how to do it, but asked the question, I'm proud of you.

It is this search meant the authors of the name Finder.

the Text is stored in computers as sequences of numbers. In the era of desktop OS every symbol is denoted by the byte number of length 8 bits. Uppercase and lowercase letters, punctuation marks, digit, space, etc – “non-printable” characters like “return line”, “beep”, “move to the next row” and the like. In our days are used much more wasteful encoding but I about them do not tell.

the engineers of the Macintosh team came up with the data type OSType, which value was a number, but on the screen appear as a sequence of 4 letters. OSType used in Mac-native the system to mnemonic symbol of the different entities.

the Type of file to display two attributes of type OSType, the first of which denotes the format (Type Code) and the second (Creator Code) if the file or application, kept the mnemonic APPL if the document type which created this application document. It is not all possible options are “Creator” and the rest (system documents, drivers, etc.) do not interest us.

Whatever way the end user sees the file may be in store MFS or HFS, the system recorded information about the attributes and the icon in a special file not visible to users. Double click on the document included in the search algorithm of the Creator of the document – the application with a file type equal to the Creator of the file. If within a disk such was not, looked for application that can work with this type of documents.

Conflicts? Happened. But much less than in PC DOS. On a Mac the file type is designated eight characters instead of three in PC DOS. Uppercase and lowercase letters in the Mac native designation of the file types differ, and nobody forbade to use as unique values for all symbols.

Multitasking

the system of the first Macs didn't support multitasking. At any time the computer runs one program, or application, or system – that is Finder.

meanwhile, in the process of developing the Mac and I quickly found the need for tools which is always handy. Calculator, alarm clock, map of the current keyboard layout and much more.

the Solution was found. Its called Desktop Accessories, or DA's. Accessories desktop. By its nature it was the drivers of a special type. They lived in RAM allocated to the running app. You can run any of them, but it could easily cause damage to their host application.

Access to DA s was carried out from the menu “Apple”, the content of which is not dependent on the running application. DA wrote not only in Apple, but third-party developers.

to be Continued.