Jednotka C: je predvolené miesto pre inštaláciu systému Windows, ak máte na svojom zariadení CD / DVD mechaniku, pravdepodobne potom bude jednotka D: a ďalšie prídavné jednotky. A čo pohony A: a B:?
Obrázok podľa Michael Holley.
Dnešná relácia otázok a odpovedí sa k nám pridelí zdvorilosťou SuperUser - podskupiny Stack Exchange, zoskupenia webových stránok Otázky a odpovede.
Otázka
Ak ste zvedač určitého vinobrania - nebudeme začať pomenovať roky - odpoveď na túto otázku je pre vás jednoznačne zrejmá. Pre mladších geekov však boli jednotky A: a B: vždy tajomne nezaznamenané na svojich počítačoch.
Čítačka SuperUser Linker3000 kladie otázku:
In Windows you have a
C:
riadiť. Všetko označené nad rámec toho je s nasledujúcim písmom.
Takže vaša druhá cesta je
D:
vaše DVD je
E:
a ak vložíte USB kľúč, stane sa to
F:
a nasledujúcu jednotku
G:
A tak ďalej a tak ďalej.
Ale potom, čo a kde
A:
a
B:
Čo a kde? Našťastie máme niekoľko skúsených geekov, ktorí odpovedali na dotaz.
Odpovede
Image
Obrázok podľa AJ Batac.
Veteran geek Adam Davis ponúka podrobný pohľad na chýbajúce písmená:
The early CP/M and IBM PC style computers had no hard drive. You had one floppy drive, and that was it. Unless you spent another $1k or so on a second floppy drive, then your system was smokin’! If you only had one drive it was common to boot from one disk, put in the other disk with your programs and data, then run the program. Once the program finished, the computer would request that you reinsert the boot disk so you could use the command line again. Copying data from one disk to the other was a series of “Please insert source disk into drive A:… Please insert destination disk into drive A:… Please insert source disk into drive A:…”
By the time hard drives became cheap, the “expensive” computers typically had two floppy drives (one to boot and run common programs, one to save data and run specific programs). And so it was common for the motherboard hardware to support two floppy drives at fixed system addresses. Since it was built into the hardware, it was thought that building the same requirement into the OS was acceptable, and any hard drives added to the machine would start with disk C: and so forth.
During the transition from 5.25″ disks (which were actually, physically floppy) to 3.5″ disks (which were encased in a harder plastic shell) it was common to have both drives in one system, and again it was supported on the motherboard with hardware, and in the OS at fixed addresses. As very few systems ran out of drive letters, it was not thought to be important to consider making those drives reassignable in the OS until much later when drives were abstracted along with addresses due to the plug’n’play standard.
A lot of software was developed since that time, and unfortunately much of it expected to see long-term storage on the C: drive. This includes the BIOS software that boots the computer. You can still attach two floppy drives, boot into DOS 6.1, and use it as you would have in the early 90’s, with floppy drives A and B.
So largely the reason for starting the hard drive at C is for backwards compatibility. While the OS has abstracted data storage to some degree, it still treats A and B differently, in such a way that allows them to be removed from the system without altering the OS, caching them differently, and due to early viruses treating their boot sector with more caution than the hard drive’s boot sector.
Príspevok SuperUser Nick sa zvoní so zaujímavou budovou anekdoty z tretieho odseku Adamovej odpovede, ktorá sa zaoberá posielaním listov:
Less an answer, more of an anecdote. In this Microsoft article, it says:
“You can assign the letters C through Z to each drive on your computer. A and B are usually reserved for floppy disk drives, but if your computer does not have floppy disk drives, you can assign A and B to volumes.”
So when I built a new computer recently with two internal drives, one for the OS and one for data, I thought, hey!, I’ll make my data drive “A”. I felt all rebellious until I discovered that Windows will not index drives lettered A or B.:(
Took me quite a while to figure out what the problem was, but I found some other people who suffered the same issue when they used A or B for a [primary] drive. As soon as I assigned that drive a different letter, windows indexed the drive. So much for being rebellious.
Toľko, že ste naozaj spurní - ak chcete žiť na okraji, môžete priradiť dátovú jednotku k A: a B:, ale nie k zavádzacej jednotke.
Máte niečo doplniť vysvetlenie? Zvuk vypnúť v komentároch. Chcete si prečítať viac odpovedí od iných používateľov technológie Stack Exchange? Pozrite sa na celý diskusný príspevok tu.
Dnešná relácia otázok a odpovedí sa k nám dostala s láskavým združením oddeleniu SuperUser - rozdelenie Stack Exchange, skupiny komunitných skupín otázok a odpovedí.
Ak ste sa niekedy pokúsili skopírovať súbor, ktorý je uzamknutý inou aplikáciou, pravdepodobne ste videli chybové hlásenie podobné ako "Proces nemôže získať prístup k súboru, pretože iný proces uzamkol časť súboru". Takže ako ho kopírujete?
Jedna nová funkcia s hlavným panelom systému Windows 7 je oznamovacia oblasť automaticky skrýva niektoré ikony. Tu sa pozrieme na to, že je trochu lepšie zvládnuteľné.
Sprievodca priečinkami umožňuje rýchly prístup k často používaným priečinkám v dvoch kliknutiach v systéme Windows 7, 64 bitov. Prečítajte si recenziu, popis a sťahovanie zdarma.
Jednotka riadenia siete umožňuje mapovať jednotlivé jednotky, vybrať jednotky, ktoré je potrebné mapovať, nastaviť časovač oneskorenia alebo systém Windows automaticky mapovať sieťové jednotky.
