Linuxnew_neterLinux(1)--LinuxLinuxwithaconsiderablelackofdetailUNIXkernelsystemprogramsapplicationprogramssystemcallsusermode()telnet(LinuxgccC)LinuxFTPLinux2.1()buffercache1NNBSDsocketvirtualfilesystem(VFS)VFSUNIXUNIXinitUNIXinitinitUNIXinit(mount)initinitsingleusermoderootshellmultiusermoderunlevels2Xinitgetty()(UNIX)initunmount()(X)gettyinitgettygettyloginloginshellshelllogininitgettySyslogsyslog2:cronat(/tmp/var/tmp)croncrontabcronatcronGUIUNIXLinuxLinuxXWindow(X)X3XAthenaMotifOpenLook2UNIXLinuxgettytelnetrloginTCP/IP(telnetrlogin)getty3gettynetworkfilesystemSunNetworkFileSystemNFSincomingmailbox()(mailtransferagentMTAsendmailsmail)(mailuseragentMUApineelm)/var/spool/mailprintqueuespools/bin,/lib,/etc,/dev,/usr/var(log)/home43Linux(LinuxFilesystemStandard)Linux(2)--LinuxFSSTNDLinuxFSSTND1.2([Qui95])Linuxport(?)LinuxLinuxLinuxdistributionsFSSTNDFSSTNDUnixUnixLinux()FSSTNDFSSTNDman/usr/var/homeLinux(CDROM)NFS(RAM)mount/usrman/usr(/usr)(/usr)mount/varspool(mailnews)logformattedmanualpages/var/usr/usr/home5()/home/home/home/students/home/staff/var/usr/usr/lib/libc.a/var/adm/messages/var/usr/var/var/usr/varUnixEmacsTeX()(manman)()/vmlinuz/bin()/sbin/bin/etc/rootroot/lib/lib/modules()/dev6/tmp/var/tmp/tmp/boot(bootstraploader)LILOIDE1024/mntmount/mnt/mnt(/mnt/dosaMSDOS/mnt/extaext2)/proc,/usr,/var,/home/etc/etcman/etc/etc/rcor/etc/rc.dor/etc/rc.dscriptsscriptsinit/etc/passwdpasswdman/etc/fdprmsetfdprmsetfdprmman/etc/fstabmount-a(/etc/rc)mountLinuxswapon-aswap4.8.5mountman/etc/group/etc/passwdgroupman/etc/inittabinit/etc/issuegetty7/etc/magicfilefilemagicfileman/etc/motdMessageOfTheDay/etc/mtabscriptsmountdf/etc/shadow/etc/passwd/etc/shadowroot/etc/login.defslogin/etc/printcap/etc/termcap/etc/profile,/etc/csh.login,/etc/csh.cshrcBourneCshellsshellman/etc/securettyroot()modem/etc/shellsshellchshshellFTPftpdshell/etc/shells/etc/termcap()/etc/termcaptermcapcurs_termcapterminfoman/dev/dev(8[Anv])/dev/MAKEDEV/dev/MAKEDEV.local()(MAKEDEV)/usr/usr/usrLinuxdistribution/usr/localdistribution/usr(FSSTND)/usr/X11R6XWindowXXX/usr/X11R6/usr/usr/X386/usr/X11R6X11Release5/usr/bin/bin/usr/local/bin/usr/sbin/usr/man,/usr/info,/usr/docGNU/usr/includeC/usr/lib/usr/libsite-widelib(library);/usr/lib/usr/local/var/var/var/catmanmancacheman/usr/man/man*man/usr/man/cat*man/var/man9(/var/catman)/var/lib/var/local/usr/local()/var/var/lock/var/lock/var/lock/var/logLoglogin(/var/log/wtmplog)syslog(/var/log/messages/var/log/var/run/var/run/utmp/var/spoolmail,news,spool/var/spool/var/spool/mail/var/tmp/tmp(/var/tmp)/proc/proc(originallyaboutprocesses,hencethename)/procprocman/proc/11/proc/proc/cpuinfo/proc/devices10/proc/dmaDMA/proc/filesystems/proc/interruptsandhowmanyofeachtherehavebeen./proc/ioportsI/O/proc/kcoreitisgeneratedontheflyasprogramsaccessit.(/proc)/proc/kmsgsyslog/proc/ksyms/proc/loadavg3/proc/meminfoswap/proc/modules/proc/net/proc/self/proc2/proc/proc/statsuchasthenumberofpagefaultssincethesystemwasbooted./proc/uptime11/proc/versionfree/proc/meminfo()Linux(3)--()()Linux(unmount)5cacheCDROM2UNIXLinux2()()()$catfilename/dev/lp1$12()cat(lpr)(/dev)lsls-l$ls-l/dev/cua0crw-rw-rw-1rootuucp5,64Nov301993/dev/cua0$crw-rw-rw-c-dblsman/dev/sdaSCSI()platterssurfacesread-writehead3600(CPU)diskcontroller()trackssectors?quot;357()51213cylinder()()fragmented()geometryCMOSRAMBIOSCMOSRAM1024translatestheaddresses820483516102435()IDESCSI(),CPUSCSILinuxcashe2-4IDE/dev/hda,/dev/hdb,/dev/hdc,/dev/hddSCSI/dev/sda,/dev/sdb,[Anv]()()(2)3.5'720KB1.44MB14/dev/fd0H1440(fd0)3.5'3.5'(H)1440KB(1440)3.5'HD[Anv]Linux/dev/fd0/dev/fd1setfdprmLinux/etc/fdprmsetfdprmcacheMSDOSCD-ROMCD-ROMbitCD-ROM(seek)15CD-ROMKB/sCDROM(LinuxdistributionsliveCD-ROM)CD-ROMCDROMISO9660MSDOSUNIXISO9660RockRidgeRockRidgeCD-ROMUNIXRockRidgeISO9660UNIXLinuxISO9660RockRidgeCD-ROMLinux(LinuxMSDOSdosemu)15CD-ROMCDROMSCSIEIDEhacking[Anv]MS-DOS(format)()low-levelformattinghigh-levelformattingUNIXformatmakeafilesystemIDESCSIBIOSMSDOSLinuxbadblocksorbadsectorsThelogictodothisisbuiltintothefilesystem;fdformat3.5'$fdformat/dev/fd0H144016Double-sided,80tracks,18sec/track.Totalcapacity1440kB.Formatting...doneVerifying...done$(/dev/fd0)setfdprm$setfdprm/dev/fd01440/1440$fdformat/dev/fd0Double-sided,80tracks,18sec/track.Totalcapacity1440kB.Formatting...doneVerifying...done$fdformat()Ifthefloppyisonlymarginallybad(duetodirtontheread/writehead,someerrorsarefalsesignals),fdformatI/Ologsyslog/usr/adm/messagesfdformat()$fdformat/dev/fd0H1440Double-sided,80tracks,18sec/track.Totalcapacity1440kB.Formatting...doneVerifying...read:Unknownerror$badblocks()3.5'2$badblocks/dev/fd0H14401440718719$badblocksmkfs()badblocksfsckmkfsfsck17222CDROMMBR(),()(MBR)BIOS()(MBR)()BIOS(Linux)(fdisk))fdisk-l:$fdisk-l/dev/hdaDisk/dev/hda:15heads,57sectors,790cylindersUnits=cylindersof855*512bytesDeviceBootBeginStartEndBlocksIdSystem/dev/hda1112410231+82Linuxswap/dev/hda22525481026083Linuxnative/dev/hda3494940815390083Linuxnative/dev/hda44094097901633055Extended/dev/hda5409409744143611+83Linuxnative/dev/hda674574579019636+83L