Smartphone Operating System (779883), страница 66
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. . ; physical . . .concepts 18, 41, 52–3, 56–58, 177, 198,199–13, 216, 237–44, 253definition 199diagrammatic overview 56–7extensions 56, 58, 210, 240LDDs 52–3, 56–58, 210–12, 239–41PDDs 52–3, 56–58, 210–11, 239–41roles 56–7, 177, 198, 199–200, 209–10,216, 243device reservations 207devicessee also hardwareasynchronous/synchronous device I/O26–29, 54–5, 84–6, 205, 236, 277concepts 8, 22–4, 25–29, 38–9, 41–2,52–58, 66, 167–68, 174–94,198–14, 225–7concurrently-shared resources 34–5, 42,69, 109–36errors 207I/O 25–29, 38–9, 50–3, 64–5, 84–6,180–1, 197–214interrupts 22–29, 35–6, 54–6, 204network communications 225–7performance considerations 29, 205–8queues 66types 201–4, 205DFC Wait state, nanothreads 77–78DFS (distributed file systems) 222–6Dial 258–9dictionary attacks, passwords 289, 292Difference Engine 7digital communications, telephony 248dining-philosophers problem,concurrently-shared resources 120–6direct memory access (DMA), concepts28–9, 203–4, 210–13318INDEXdirect model, memory implementation models161–2direct (random) access, files 174–5, 205directories 32, 159–3, 167–95see also filesattributes 169–1, 179–2concepts 167–95definition 168files 32, 167–95historical background 169names 171, 179–80page directories 159–3paths 168–1sizes 179structures 179–2table of contents 170–1Unix 180disks 12, 28–9, 31, 138, 145–6, 163,167–68, 177, 180–5, 305see also files; secondary storageclusters 177, 181components 177cylinders 177defragmentation 182DMA 28–9, 203–4FAT file systems 42, 182–5fragmentation problems 180–2mainframe computers 12partitions 168–9, 179sectors 177, 181storage-free computers 223–5tracks 177types 31, 177virtual disks 305dispatchers, operating systems 91–4displayssee also screensdouble buffering 206LCD management 210–11distributed file systems (DFS) 222–6distributed systemssee also networksconcepts 13–14, 219–6historical background 13–14models 14DLLs see dynamically loaded librariesDMA (direct memory access) 28–9, 203–4,210–13DOC files 169DoCancel 84–6DomainOS 14, 221domains 161double buffering 206drives 212DVDs 188dynamic loading, concepts 143–5, 148–4,243dynamic memory 49, 51, 143–5, 148–6,160–1dynamically loaded libraries (DLLs) 49,52–3, 139–1, 143–5, 155–6, 303–4loading issues 155–6memory management 143–5, 155–6stubs 144–5, 160ECOMM.LDD 210, 240ECUART 241–2electronic disks 31see also diskselectronic mail (email) 53, 236–7, 263,265–68, 271, 274–6, 280, 282–3see also messagingELF format Solaris files 157email (electronic mail) 53, 236–7, 263,265–68, 271, 274–6, 280, 282–3see also Internet; messagingemulator, concepts 161–2, 251, 302, 303–4encryption 186, 289–90ENET.LDD 240ENIAC 7environmental issuesclosed environments 215–16concurrently-shared resources 110–12connected environments 217–28EPOCsee also Symbian OShistorical background 10–11, 19, 42, 305INDEXepochs, Linux 103–4Ericsson 11, 247errno 207errorsI/O 207socket streams 131Symbian OS 160ESDRV.PDD 240ESOUND.LDD 240ETelCall abstraction 251, 257–60concepts 247, 249, 251–60, 295Line abstraction 251, 256–7Phone abstraction 251, 254–5Ethernet 226, 238, 240ETHERNET.PDD 240events, active objects 73–4, 76–79, 83–6,212–13, 236–7evolution, operating systems 17–19exceptionserrors 160interrupts 24executable files 139–1see also processesexecution in-place issues, memorymanagement 155execution libraries 8execution timesexecution-time binding 139–1interrupts 55, 105–6predictions 105–6executive calls 42–3exit 81–2extensibility needs, operating systems 6–7extensionssee also application-specific .
. . ;bootstrap . . . ; device driversconcepts 56, 58, 169–70, 210, 240files 169–70, 172external fragmentation, concepts 149–50,181–2F32 295319fast Semaphore Wait state, nanothreads77–78FAT file systems 42, 182–5, 188–9fault tolerance, file systems 186fax 251, 272–3, 276, 280see also messagingFCBs (file control blocks) 178, 179–2FCFS see first-come-first-served strategyfetch–execute cycle (core computing cycle)29, 204FIFO queues 90file control blocks (FCBs) 178, 179–2file servers 39, 42, 48–9, 53, 57, 93, 178,187–88, 190–4, 211–12, 222–6see also RF...; serversnaming considerations 222–3networked file systems 222–6replicated files 224file systemssee also storage structuresabstraction principles 167, 175–6access rights 32, 33–38, 189–4building blocks 167–75concepts 32, 42, 167–95, 216, 222–6FAT file systems 42, 182–5, 188–9fault tolerance 186generic implementation layers 175–78implementation issues 175–88Microsoft Windows 42, 170–2, 182–3,188–90mobile phones 188–9, 193–4networks 222–6NTFS 185–6, 305permissions 190–4remote file systems 187–88roots 171, 180, 190, 279security issues 189–4Symbian OS 42, 193–4, 227Unix 186–7, 191–2, 305VFAT file system 183–5files 32, 39, 41–2, 167–95, 216, 222–6see also databases; directories; disksaccess issues 170–1, 174–5, 181, 189–4applications 171–2, 178320INDEXfiles (continued )attributes 169–1, 179–2binary files 168–9close operations 173, 178concepts 32, 39, 41–2, 167–95, 216create operations 172–3date/time of access 170–1, 181definition 167–68defragmentation 182delete operations 174direct (random) access 174–5, 205extensions 169–70, 172group identification 170–1, 190–4historical background 169, 182–5, 216identification issues 170–1, 190–4indexed access 175Linux 170–2, 188–9, 192–3logical/physical files 170–1, 178, 181–2Microsoft Windows 42, 170–2, 182–5,188–90, 223, 288names 169, 171, 181, 222–3open operations 173, 178, 179operation types 172–4, 178, 192–4owners 170–1, 181, 190–4partitions 168–9, 179pathnames 171, 222–3performance considerations 180–2,206–8read operations 173, 178, 192, 205, 209replication benefits 224reposition operations 173roots 171, 180, 190, 279sequential access 174–5, 205sizes 170–1, 181–3structural issues 168–9, 171–95tables 170–1, 174, 178truncate operations 174types 168–70users 170–1, 190–4write operations 173, 178, 194, 205, 209finger example, security issues 286, 292fingerprints 291Firewire 199first-come-first-served strategy (FCFS), processscheduling 94–6, 98, 116flags, synchronization operations 114–15flash storage 2, 31, 52, 146, 154, 167–68,177, 188–9FMSignal 127FMWait 127folders 32, 168, 277–79see also directoriesfork 79–1, 124–6forking issues, processes 72, 79–2, 124–6formats, message characteristics 265–7,273–5fragmentationdisks 180–2memory 149–50frames, physical memory 146–7, 159–1,162–3free space, storage media 182FreeBSD 91FSSignal 127FSWait 127function calls 5–6, 36, 42–3, 47, 49, 52–4,69–1, 76, 79–2, 207–9, 231–2, 279gatekeeper security model 294–6gateway servers 232general communications concepts 230–1,237see also communicationsGeneral Electric 8generic implementation layers, file systems175–78Gentoo Linux 14GetPhoneInfo 253–4Gif files 168, 272global memory 50, 128GPRS networks 226graphical user interfaces (GUIs)asynchronous device I/O 28historical background 13–16process scheduling 97The Great Wall of China 285INDEX321group identification, files 170–1, 190–4GSM protocol 57, 105, 234, 248, 250–1,254–5, 260, 263, 269–3GUIs see graphical user interfacesHTML pages 232HTTP 227, 232, 293human level, security issues 286–7, 292hybrid kernels, concepts 21–2HAL (hardware-abstraction layer) 210–11handheld computers 9–10, 14–15, 28,154–5, 247, 306constraints 14–15, 154–5historical background 9–10, 14–15, 247HangUp 260Hansen, Per Brinch 120hard disks see diskshard real-time systemssee also real-time .
. .concepts 16, 101–2hardwaresee also CPU; devices; disk . . . ; memory . . .access issues 32–38, 170–1, 174–5concepts 2–11, 17–45, 62–3, 156,167–68, 174–94, 198–14, 237–42concurrently-shared resources 34–5, 42,69, 109–36definition 3goals 3–4historical background 7–16, 33I/O issues 201–4interrupts 22–29, 35–6, 54–6, 204kernel structures 20–2, 47–59memory offloads 156new hardware 301–2operating systems 1–16, 17–45, 109–36protection issues 33–38, 48–9, 189–4,301–2virtual machines 300–8hardware-abstraction layer (HAL) 210–11Hayes command set, modems 248headers, messaging 265–71, 273–5, 278–9heaps, concepts 149, 155, 156–7, 161, 306hexadecimal 269–70hidden scheduling problems 104Hoare, C.A.R.
120host operating systems, concepts 300–8I/O 25–29, 38–9, 50–3, 64–5, 84–6,180–1, 197–214, 216, 225–7, 249–50abstraction principles 198, 204–5,210–11, 303blocking/nonblocking I/O 208–9,212–13buffers 206–7buses 198–14communications models 229–46,249–50components 198–1concepts 197–214, 216, 225–7, 229–46device controllers 22–4, 198–1, 216device drivers 198, 199–13diagrammatic overview 201DMA 203–4, 210–13errors 207hardware issues 201–4interrupts 204kernel structure 205–8, 210memory-mapped I/O 202–4network communications 225–7performance considerations 29, 180–1,205–7polling 203–4registers 202–4removable storage media 212–13sockets 39, 49, 130–2, 225–7, 235,243–5software issues 204–13spools 206–7Symbian OS 209–13timers 207–8types 198–1IBM350 disk file 169MS-DOS 8–9, 13, 19, 36, 169, 182–3MVS 40–1322INDEXIBM (continued )OS/360 8, 12, 40–1SMB 225identification issuesfiles 170–1, 190–4processes 32, 64, 66–7, 74, 113–16,287–88idle processes 100–1image filessee also filesconcepts 168, 272–3IMAP (Internet Message Access Protocol)268, 275–6IMC (Internet Mail Consortium) 272indexed access, files 175infrared connectivity 9, 10, 50–1, 226, 238,240–2, 249, 271, 272Initialize 255InitL 253–61inputsee also I/Oconcepts 3–7, 197–214Intel chips 1, 8–9, 36, 162interdependent distributed systems, concepts14interface designs 2interleaving processes 111–12, 207internal fragmentation, concepts 149–50,181–2International Telecommunication Union (ITU)273Internet 10–11, 14, 33–5, 39, 47, 67–68,218, 226, 232–5, 267, 268, 272, 275–6see also email; webInternet Engineering Task Force 267Internet Mail Consortium (IMC) 272Internet Message Access Protocol (IMAP)268, 275–6interprocess communication (IPC)concepts 128–2mail model 129phone model 129–30RPCs 130, 132sockets 130–2, 235Symbian OS 132interrupt service routines (ISRs) 23–5, 52–3,55–6, 204interrupt-request line 204interruptssee also system function callsbootstrap programs 24–5concepts 22–29, 35–6, 43, 49, 52–6, 72,91–4, 104–6, 204context-switches 25, 37–38, 40–1,49–50, 55, 74, 76, 82, 91–102,145–6, 156definition 23–4, 54dispatchers 91–4exceptions 24execution times 55, 105–6I/O 204implementation 54–6, 91–4latency requirements 55, 92, 103–4, 106maskable interrupts 24operating systems 22–29, 35–6, 43, 49,52–6, 72, 91–4, 104–6, 204phases 55–6priorities 55–6, 98, 104–6interval timers 208ioctl 205, 249IP addresses 218–19IPC see interprocess communicationIR see infrared .
. .IrCOMM 242ISO networking model 232–4ISRs (interrupt service routines) 23–5, 52–3,55–6, 204IsSupportedByModule 253–4ITU (International Telecommunication Union)273Java 43, 299, 303–7ME 305–6, 307virtual machine (JVM) 299, 303–7JFFS 189jobssee also processesINDEXmainframe systems 11–13, 62scheduling 12, 40–1join operations, process programming 79–2Jpeg files 168, 272JVM (Java virtual machine) 299, 303–7KERN-1 EXECerror 160kernelsee also micro . . . ; monolithic .
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