ݺߣ

ݺߣShare a Scribd company logo

Linux: Presmerovanie I/O

?
?
M
Michal Sedlak
1 of 43
Download to read offline
LinuxFEST 7.3.2009 GNU/Linux Presmerovanie I/O Autor: Michal Sedlk Email: michal6103 [at] gmail [dot] com
Prezentcia je zalo?en na The LBook: An Introductory Guide to Linux Basics http://linuxbasics.org/course/book/index Vizulna tma prezentcie je odvoden tmy vytvorenej: Sakari Koivunen and Henrik Omma Released under the LGPL license. 7.3.2009 2/40
Obsah Jednoduch presmerovania C ?tandardn? vstup a v?stup C Opertory Pokro?il presmerovania C File deskriptor Filtre 7.3.2009 3/40
Presmerovanie Zachytenie v?stupu C Sboru C Prkazu C Programu C Skriptu C Bloku kdu v skripte Poslanie na vstup C Sboru, prkazu, programu, alebo skriptu 7.3.2009 4/40
Input, Output, Error Program C Standard input Klvesnica C Standrad output Obrazovka Tla?iare Sbor C Standard error 7.3.2009 5/40
Opertory > a | prikaz > subor C Presmeruje stdout do sboru C Ak sbor neexistuje, tak bude vytvoren? C Ak sbor existuje, bude prepsan? prikaz1 | prikaz2 C Presmeruje stdout prkazu jedna do stdin prkazu dva 7.3.2009 6/40
Prklad > $?cat?>?test1 Toto?sa?zapise?do?suboru $?cat?>?test2 Toto?sa?zapise?do?ineho?suboru $?cat?test1 Toto?sa?zapise?do?suboru $?cat?test2 Toto?sa?zapise?do?ineho?suboru 7.3.2009 7/40
Prklad > #zl? enie?sborov?test1?a?test2? $?cat?test1?test2?>?test3 $?cat?test3 Toto?sa?zapise?do?suboru Toto?sa?zapise?do?suboru?test2 7.3.2009 8/40
Prepsanie sborov >| Noclobber C bash ochrana (.bashrc) $?set??o?noclobber ?cat?>?test3 bash:?test3:?ned?sa?prepsa? ?existujci?sbor $?cat?>|?test3 prepisal?som?subor?test2???????? $?cat?test3 prepisal?som?subor?test2 $?set?+o?noclobber 7.3.2009 9/40
Vytvorenie sboru $?ls??la celkom?12 drwxr?xr?x???2?michal?michal?4096?2009?03?06?18:17?. drwxr?xr?x?161?michal?michal?8192?2009?03?06?18:17?.. $?>?prazdny?subor $?ls??la celkom?12 drwxr?xr?x???2?michal?michal?4096?2009?03?06?18:17?. drwxr?xr?x?161?michal?michal?8192?2009?03?06?18:17?.. ?rw?r??r?????1?michal?michal????0?2009?03?06?18:17?prazdny?subor 7.3.2009 10/40
Sie? /dev/tcp/host/port /dev/udp/host/port Vypnut v Debiane: C nepredvdate?n d?sledky C Netcat C /usr/share/doc/bash/README.Debian.gz 7.3.2009 11/40
Rra | Presmerovanie v?stup jednho programu do druhho grep retazec1 subor | grep -v retazec2 ls -la | less cat script | mysql 7.3.2009 12/40
Rra | $?ls?/dev?|grep?sda sda sda1 sda2 sda3 sda5 7.3.2009 13/40
Prklad < Presmerovanie obsahu sboru do ?tandardnho vstupu programu $?ls?Obrzky/ Avatar??Experimenty??Webcam $?ls?Obrzky/?>?dir.txt $?cat?dir.txt?|?sort??r Webcam Experimenty Avatar $?sort??r?<?dir.txt Webcam Experimenty Avatar 7.3.2009 14/40
Kombinovanie opertorov Opertory sa daj kombinova? $?sort??r?<?dir.txt?>?reversed.txt $?cat?reversed.txt? Webcam Experimenty Avatar $?less???help?|?grep??i?examine?>?examine.txt $?cat?examine.txt? ??:e?[file]?????????Examine?a?new?file. ??:n?????????????*??Examine?the?(N?th)?next?file ??:p?????????????*??Examine?the?(N?th)?previous?file ??:x?????????????*??Examine?the?first?(or?N?th)?file ??+cmd??????????????Execute?the?less?cmd?each?time?a?new?file 7.3.2009 15/40
Kombinovanie opertorov ?ubovo?n? po?et | Niektor programy nepou?vaj stdin a stdout (?tajte man strnky) 7.3.2009 16/40
Opertor >> Pripojenie stdout na koniec sboru Ak sbor neexistuje, tak vytvor sbor Ak sbor existuje, tak ho roz?ri o v?stup spustenho programu 7.3.2009 17/40
Prklad >> $?date?>>?datum.txt $?date?>>?datum.txt $?date?>>?datum.txt $?date?>>?datum.txt $?date?>>?datum.txt $?cat?datum.txt? Pi?mar??6?20:59:46?CET?2009 Pi?mar??6?20:59:48?CET?2009 Pi?mar??6?20:59:49?CET?2009 Pi?mar??6?20:59:50?CET?2009 Pi?mar??6?20:59:51?CET?2009 7.3.2009 18/40
File deskriptor Pridelen? ka?dmu otvorenmu sboru ?slo pridelen OS Identifiktor sl?iaci na poskytnutie prstupu Pre pou?vate?a 0-9 exec (3 -Ubuntu, 5-LDP) 7.3.2009 19/40
/dev/fd $?ls??la?/dev/fd /dev/fd??>?/proc/self/fd $??ls??la?/dev/fd/ $??ls??la?/dev/fd/ 0??>?/dev/pts/1 0??>?/dev/pts/0 1??>?/dev/pts/1 1??>?/dev/pts/0 2??>?/dev/pts/1 2??>?/dev/pts/0 3??>?/proc/7381/fd 3??>?/proc/7381/fd 7.3.2009 20/40
0,1,2 File deskriptor 3 typy I/O C standard input: FD 0 C standard output: FD 1 C standard error: FD 2 ?sla s s identifiktory C > je ekvivalent k 0> C < je ekvivalent k <1 7.3.2009 21/40
Prklad 1> a 2> $?mkdir?testdir $?cd?testdir $?>?file1 $?ls File1 $?ls?file1?file2? ls:?nie?je?mo?n?pristupova? ?k?file2:?No?such?file?or?directory?File1 $?ls?file1?file2?1>?dirlist?2>?errorlist $?cat?dirlist File1 $?cat?errorlist ls:?nie?je?mo?n?pristupova? ?k?file2:?No?such?file?or?directory 7.3.2009 22/40
>N vs. >&N >N C Presmerovanie do suboru N >&N C Presmerovanie na FD N 7.3.2009 23/40
stderr a stdout v jednom sbore $?ls?file1?file2?>?dirlist?2>&1 $?cat?dirlist ls:?nie?je?mo?n?pristupova? ?k?file2:?No?such?file? or?directory file1 $?ls?file1?file2?&>?dirlist $?cat?dirlist ls:?nie?je?mo?n?pristupova? ?k?file2:?No?such?file? or?directory file1 $?ls?file1?file2?2>&1?>?dirlist ls:?nie?je?mo?n?pristupova? ?k?file2:?No?such?file? or?directory $?cat?dirlist? file1 7.3.2009 24/40
Prezeranie ch?b Ak program generuje ve?a ch?b command 2>&1 | less 7.3.2009 25/40
Bash 4 (23. 2. 2009) &>> ekvivalent cmd >>subor 2>&1 |& ekvivalent cmd 2>&1 | cmd 7.3.2009 26/40
Presmerovanie ch?b Presmerovanie ch?b do inho terminlu $?tty /dev/pts/1 $?make?2>?/dev/pts/0 $?tty /dev/pts/0 $?make:?***?No?targets?specified?and?no? makefile?found.??Stop. make:?***?No?targets?specified?and?no?makefile? found.??Stop. 7.3.2009 27/40
Zapisovanie do sborov a zrove na obrazovku $?ls?file1?file2?|?tee?dirlist? ls:?nie?je?mo?n?pristupova? ?k?file2:?No?such?file? or?directory file1 $?cat?dirlist? file1 $?ls?file1?file2?2>&1?|?tee?dirlist? ls:?nie?je?mo?n?pristupova? ?k?file2:?No?such?file? or?directory file1 $?cat?dirlist? ls:?nie?je?mo?n?pristupova? ?k?file2:?No?such?file? or?directory file1 7.3.2009 28/40
Vypisovanie ch?b v skriptoch $?echo?Chybova?hlaska?>&2 Chybova?hlaska case?"$1"?in ??start) #?No?op ;; ??restart|reload|force?reload) echo?"Error:?argument?'$1'?not?supported"?>&2 exit?3 ;; ??stop) do_stop ;; ??*) echo?"Usage:?$0?start|stop"?>&2 exit?3 ;; 7.3.2009 29/40
Vytvorenie FD N<> Zatvorenie FD n<&-, n>&- $?echo?1234567890?>?File $?exec?3<>?File $?read??n?4?<&3 $?echo??n?.?>&3 $?exec?3>&? $?cat?File 1234.67890 7.3.2009 30/40
Prklad <<a <<- Here documents #!/bin/bash interactive-program <<-LimitString command #1 command #2 ... LimitString 7.3.2009 31/40
Trval presmerovanie exec exec - vytvorenie novho procesu, nahradenm starho exec ovplyvn presmerovanie, pre cel? skript, alebo shell (PID) exec >filename (cely shell, skript) > filename (len pre novo forknut procesy) 7.3.2009 32/40
Prklad na exec #!/bin/bash exec?6<&0??????????#?zapametame?si?stdin exec?<?data?file???#?nahradime?stdin?s?"data?file" read?a1????????????#?nacitame?prvy?riadok?z?"data?file". read?a2????????????#?nacitame?druhy?riadok?"data?file." echo?$a1 echo?$a2 echo;?echo;?echo exec?0<&6?6<&??????#?vratime?hodnotu?stdin?a?zmazeme?fd6 echo??n?"Enter?data??" read?b1????????????#?citanie?z?klavesnice. echo?"b1?=?$b1" exit?0 7.3.2009 33/40
Filtrovanie v?stupu grep cut sort sed 7.3.2009 34/40
grep Vyh?adva v sboroch, alebo zo stdin $?grep?users?/etc/group users:x:100:dusko,michal,marticka vboxusers:x:1001:michal michal@axserver:~$?ps??ef?|?grep?apache root??????2445?????1??0?Feb28???????/usr/sbin/apache2??k?start michal????2905??2891??0?11:57?pts/0?grep?apache www?data?21638??2445??0?Mar01???????/usr/sbin/apache2??k?start www?data?25639??2445??0?Mar02???????/usr/sbin/apache2??k?start michal@axserver:~$?ps??ef?|?grep?apache?|?wc ??????4??????39?????285 7.3.2009 35/40
cut $?ls??la?|?cut??c?35?50 2009?03?07?12:08 2009?03?07?10:39 2009?03?07?12:06 2009?03?07?12:06 $?ls??la?|?cut???d"?"??f?12,13 12:06?a 12:06?b 12:06?c 12:08?d 12:08?e 12:08?f 12:08?g 7.3.2009 36/40
sort Zoradenie pod?a michal@doma:~/testdir$?ls?|? sort??r r?znych kriteri g f e -r reverse d c -R random b a michal@doma:~/testdir$?ls?|? -u iba uniktne sort??R g e b d c f a 7.3.2009 37/40
sort $?ls??la?|?cut??c?35?50 2009?03?07?12:08 2009?03?07?10:39 2009?03?07?12:06 2009?03?07?12:06 2009?03?07?12:06 2009?03?07?12:08 2009?03?07?12:08 2009?03?07?12:08 2009?03?07?12:08 $?ls??la?|?cut??c?35?50?|?sort??u 2009?03?07?10:39 2009?03?07?12:06 2009?03?07?12:08 7.3.2009 38/40
sed Stream editor Regulrne v?razy $?echo?Windows?je?dominantny?OS?a?Balmer?je?stastny?|?sed?' s/Windows/Linux/ s/stastny/nestastny/' Linux?je?dominantny?OS?a?Balmer?je?nestastny 7.3.2009 39/40
Zhrnutie Presmerovanie Opertory >, >>, &>, &>>, |&, | File deskriptory >&, <>, <&-, >&- exec Filtre grep, cut, sort, sed 7.3.2009 40/40
?akujem za pozornos? Na prpadn otzky rd odpoviem michal6103 [at] gmail [dot] com 7.3.2009 41/40
LinuxFest podporuj
Referencie http://tldp.org/LDP/abs/html/io-redirection.html

More Related Content

Linux: Presmerovanie I/O