1 / 38

Unix Utility 常用的工具程式

Unix Utility 常用的工具程式. Instructors: Fu-Chiung Cheng ( 鄭福炯 ) Associate Professor Computer Science & Engineering Tatung Institute of Technology. Outline. System(Process)-related utilities (chap 7) Text File utilities (chap 8). Display Date and Time.

rosina
Download Presentation

Unix Utility 常用的工具程式

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Unix Utility常用的工具程式 Instructors: Fu-Chiung Cheng (鄭福炯) Associate Professor Computer Science & Engineering Tatung Institute of Technology

  2. Outline • System(Process)-related utilities (chap 7) • Text File utilities (chap 8)

  3. Display Date and Time • date command show current time and date. $ date Mon May 4 09:01:03 EST 1999 $ date ‘+%a %d:%m:19%y’ Mon 04:05:1999 $ date ‘+It is exactly %H:%M and %S seconds.’ It is exacly 09:01 and 03 seconds. • format: • A. %H: hour(two digits) • B. %M: minute (two digits) • C. %S: second (two digits)

  4. Date command • other format: • C. %a: day(Sun, Mon, Tue, Wed, Thu, Fri, Sat) • D. %w: day(0..6) 0 is Sunday • E. %j: Julia day (001..366) • F. %m: month (two digits) • G. %d: date (two digits) • H. %y: year (two digits) • I. %T: time in HH:MM:SS (24 hour format) format • J. %n: new line • supre user can change date. >date mmddhhnn[yy] • mm:month dd:date hh:hour nn:minute yy:year

  5. List logged-in Users • who command displays information about the current • status of the system • whoami: list user‘s information $ who john tty01 May 5 09:01 dan tty17 May 5 09:02 $ who -uH … $ whoami …

  6. List users‘ information • finger command lists the information of users in the • system: • A. Name and where (office): from /etc/password • B. when: login time • C. idle time: $ finger Login Name TTY Idle When Office john John Cheng 01 Mon 09:01 cs522 dan Dan Quale 17 2d Sat 19:02 EE20

  7. List users‘ information • finger userName@remoteHost (or IP) • A. show detail information of userName@remoteHost • B. .plan file .project (unix predefined files) • C. try to use editor to add some information to .plan • and/or .project $ finger cheng@140.129.20.247 ...

  8. Change Login Password • passwd command: change your logic password $ passwd Old password: New Password: Retype Nnew password: $

  9. Change Login Password • Good Practice: change your password frequently • A. length of password > 5 char • B. users may change their own passwords • C. super user can change the password of any user • super user can have more option • -d delete password -a list all users

  10. Processes • A process is a program that is being executed. • Invoke two emacs programs and one vi program • Processes are kept in kernel’s process table. • Process-related commands: ps, kill, nice, time, nohup $ emacs & $ vi & $ emacs &

  11. List Processes • ps command: list your processes • the options of ps may different platforms (use man ps) • each process has a process identification number (pid) • some options: • -e all processes • -f all information • -p pid • -t tty • -u uid $ ps PID TTY TIME COMD 26344 02 0:14 -sh 29313 02 0:01 -ps $ ps -p 2150

  12. Kill Processes • You may use Ctrl-C to kill a forground process • to kill a background process: use kill command • how to make a background process: $textedit & • how to make a background process forgrond: $fg • How to use kill? • A. use ps to find • out the pid . • B. kill pid or • kill -9 pid $ ps PID TTY TIME COMD 26344 02 0:14 -emacs 29313 02 0:01 -ps $ kill -9 26344 $

  13. Run Programs while logged off • nohup (no hangup) command: continue to execute a • process after logout. $ nohup nroffbook & 29673 Sending output to ‘nohup.out’

  14. Run processes at lower priority • nice: run processes with lower priority. • Examples: • A. >nice program & • B. >nice -5 program • C. >nice --5 program (superuser only) • niceness value: 1-19 (higher value => lower priority). $ nice nroffbook & 29673 $ nice nohup nroffbook & 29678 Sending output to ‘nohup.out’

  15. Time Prcesses • time command: measure running time of a process. • A. wall time:total elapsed time • B. user time: execution time (I/O) • C. CPU time: system time $ time nroffbook 338.8 213.7 26.5 $

  16. Display Message • echo command displays message to console. • echo “What is the beginning and end of eternal life?” $ echo ‘just display’ just display $ echo just display just display $ echo $PATH :/bin:/usr/bin:/usr/local/bin:/home/kc/bin $

  17. Communication with other users • write, talk, ntalk: communication with other user • Examples: • A. write userName • B. talk userName@host • write: communication within the same host • talk, ntalk: communication through network • mesg -n: do not want to talk to anyone $ talk userB@IP Waiting for connect... $ talk userA@IP

  18. Set/Display terminal information • tty, stty: set or display terminal information • Examples: • A. tty • (the terminal information may be used in write command) • B. stty • C. stty erase \^h kill \^u intr \^c (keyboard setting) $ stty speed 9600 baud; rows=25; columns=40 … $ stty erase \^h $ tty /dev/pts002 $ ls -l /dev/pts002

  19. Chap 8Text File Untilities

  20. Type Files • cat command concatenates files to standard output. • Examples: • A. cat file • B. cat file1 file2 file3 > files • C. cat file[123] >files • D. cat file? > files • E. cat file* > files • F. cat /dev/null > empty • G. cat > stdout • note that cat file3 file1 > file31 but • cat file[31] > file13 $ cat /etc/motd system will be down all weekend for equipment installation $ cat /etc/greeting welcome to Unix $ cat /etc/greeting \ /etc/motd

  21. Format Files • pr command: format one or more files • Examples • A. >pr -h head -l15 file • B. >pr -3 -l12 file • C. >pr -3 -a -l12 file • D. >pr -n • try: • A. ls > temp1 • B. pr -h cheng -l15 temp1 $ cat verse Birds can fly Cats are fun Dogs sniff Fish can swin I like monkey $ pr -3 -l12 verse ...

  22. fmt command • fmt: fill and join text, producing lines of roughly the same • length • Examples: • A. fmt -w 65 filename

  23. Print Files • lp: send file to printer (lpr) • Examples: • A. lp -n 5 (5 copies) -m (send mail) report • B. ls -l /bin /usr | pr | postprint |lp -d ps

  24. Browse Text File • pg: display files on a terminal, one page at a time. • Examples: • A. pg file1 file2 • B. pg -p ‘Page%d :’ file • Prompt: • A. Enter: next page -1Enter: previous page • B. q or Q: quit pg • C. h for help

  25. Count Lines, words and Characters • wc command: print the counts of character, words, lines • Examples: • A. wc file • B. wc -w file • C. who | wc -l • D. wc file* $ wc chapt? 408 2007 12093 chapt1 684 7921 32313 chapt2 1071 11040 45818 chapt3 509 7210 29289 chapt4 606 7680 30910 chapt5 3278 35838 150532 total

  26. Compare files • diff: report the lines that differ between file1 and file2 • Examples: • A. diff file1 file2 • < file1... • > file2... • B. diff -w file1 file2 $ diff arlinote arlinote2 5c5 < ice rink. --- >ice skating rink. 10all >Susan - 586-1234

  27. Compare files • diff3: report the lines that differ between three files • $diff3 file1 file2 file3 • ==== all three files differs • ====1 file 1 different • ====2 file 2 different • ====3 file 3 different

  28. Sorting File • sort: sort the lines of the files in alphabetical order • Examples: • A. wc -l *|sort -r • B. sort +2n -t: /etc/passwd • +2 skip two fields • n sort in arithmetic order • C. build telnos as shown in textbook • try >sort telnos • >sort +1 telnos • >sort telnos > telnos.temp • D. sort +0.1 -0.2 /etc/passwd $ cat telnos kc 362-4993 gmk 245-3209 arm 333-3903 $ sort telnos arm 333-3903 gmk 245-3209 kc 362-4993 $ sort +1 telnos gmk 245-3209 arm 333-3903 kc 362-4993

  29. Search Text Patens in Files • grep, egrep, fgrep: search one or more files for lines • that match a regular expression. • Exit status: 0: if any lines match • 1: no lines match • 2. Error • Examples: • A. grep userName /etc/passwd • B. grep “any string to be searched” /usr/include/* • C. grep “any string to be searched” /usr/include/*/* • D. grep -i string files

  30. Search Text Patens in Files • fgrep: fast grep (does not support regular expression.) • egrep: support different regular expression (see manpage)

  31. Rearrange Columns of Files • cut: select a list of columns or fields form one or more files • -d delimiter (default is tab) • -f fields to be kept • -c fields to be cut • Examples: • A. cut -d: -f1,5 /ect/passwd • B. who |cut -d” “ -f1 • C. cut -c4 file|paste - file $ cat telnos kc 362-4993 gmk 245-3209 arm 333-3903 $ cut -f1 telnos kc gmk arm $

  32. Rearrange Columns of Files • paste: merge corresponding lines of one or more files • into a vertical columns, separated by a tab. $ cat telnos kc 362-4993 gmk 245-3209 arm 333-3903 $ cut -f1 telnos >names $ cut -f2 telnos >nums $ paste nums names >newtelnos 362-4993 kc 245-3209 gmk 333-3903 arm $

  33. Rearrange Columns of Files • paste options: • -d delimiter (default is tab) • - replace a filename with the standard input • Examples: • A. paste f1 f2 f3 > file123 • B. who | paste -d -

  34. Translate Characters • tr: copy standard input to standard output, and • perform substitution. • Examples: • A. cat file | tr ‘[A-Z]’ ‘[a-z]’ • B. tr ‘ ‘ ‘\012’ < file $ cat numbs 1,300.5 900.35 1,333,545.80 $ tr ., ,. <numbs 1.300,5 900,35 1.333.545,80

  35. Find Spelling Error • spell: compare the words of files with system dictionary • Examples: • A. spell file file2 >jargon

  36. Encode Files • crypt: encrypt a file to prevent unauthorized access. • Examples: • A. crypt encryptKey <infile > outfile $ cat numbs 1,300.5 900.35 1,333,545.80 $ crypt xyzzy321 <numbs >numbs.cry

  37. Duplicate File • tee: read standard input and diverts it both to the standard • output and to one or more named files. • Example: • $spell chapt5 | tee errwords

  38. Print the first/last few lines of a files • head: print the fist few line • tail: print the last few line • Examples: • A. grep “pid_t” /usr/include/* |head -20 • B. grep “pid_t” /usr/include/* |tail -20 $ echo “one\ntwo\nthree\nfour\nfive” > num $ head -3 num $tail -3r num one five two four three three

More Related