Журнал лабораторных работ

Содержание

Журнал

Среда (10/22/14)

/dev/pts/2
10:48:16
#sed 's/:/ /g' /etc/passwd
root x 0 0 root /root /bin/bash
daemon x 1 1 daemon /usr/sbin /bin/sh
bin x 2 2 bin /bin /bin/sh
sys x 3 3 sys /dev /bin/sh
sync x 4 65534 sync /bin /bin/sync
games x 5 60 games /usr/games /bin/sh
man x 6 12 man /var/cache/man /bin/sh
lp x 7 7 lp /var/spool/lpd /bin/sh
mail x 8 8 mail /var/mail /bin/sh
news x 9 9 news /var/spool/news /bin/sh
...
backup x 34 34 backup /var/backups /bin/sh
list x 38 38 Mailing List Manager /var/list /bin/sh
irc x 39 39 ircd /var/run/ircd /bin/sh
gnats x 41 41 Gnats Bug-Reporting System (admin) /var/lib/gnats /bin/sh
nobody x 65534 65534 nobody /nonexistent /bin/sh
libuuid x 100 101  /var/lib/libuuid /bin/sh
Debian-exim x 101 103  /var/spool/exim4 /bin/false
user x 1000 1000 user,,, /home/user /bin/bash
sshd x 102 65534  /var/run/sshd /usr/sbin/nologin
student x 1001 1001  /home/student /bin/bash
10:48:28
#sed 's/:/\n/g' /etc/passwd
root
x
0
0
root
/root
/bin/bash
daemon
x
1
...
102
65534
/var/run/sshd
/usr/sbin/nologin
student
x
1001
1001
/home/student
/bin/bash
10:48:52
#sed 's///-/g' /etc/passwd
sed: -e выражение #1, символ 5: неизвестный модификатор к `s'
10:49:04
#sed 's///-/g' /etc/passwd
sed: -e выражение #1, символ 5: неизвестный модификатор к `s'
10:49:16
#sed 's/'/'/-/g' /etc/passwd
sed: -e выражение #1, символ 5: неизвестный модификатор к `s'
10:49:26
#sed 's/ /-/g' /etc/passwd
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/bin/sh
bin:x:2:2:bin:/bin:/bin/sh
sys:x:3:3:sys:/dev:/bin/sh
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/bin/sh
man:x:6:12:man:/var/cache/man:/bin/sh
lp:x:7:7:lp:/var/spool/lpd:/bin/sh
mail:x:8:8:mail:/var/mail:/bin/sh
news:x:9:9:news:/var/spool/news:/bin/sh
...
backup:x:34:34:backup:/var/backups:/bin/sh
list:x:38:38:Mailing-List-Manager:/var/list:/bin/sh
irc:x:39:39:ircd:/var/run/ircd:/bin/sh
gnats:x:41:41:Gnats-Bug-Reporting-System-(admin):/var/lib/gnats:/bin/sh
nobody:x:65534:65534:nobody:/nonexistent:/bin/sh
libuuid:x:100:101::/var/lib/libuuid:/bin/sh
Debian-exim:x:101:103::/var/spool/exim4:/bin/false
user:x:1000:1000:user,,,:/home/user:/bin/bash
sshd:x:102:65534::/var/run/sshd:/usr/sbin/nologin
student:x:1001:1001::/home/student:/bin/bash
10:49:38
#sed 's/:.*//' /etc/pa
pam.conf  pam.d/    passwd    passwd-
10:49:38
#sed 's/:.*//' /etc/passwd
root
daemon
bin
sys
sync
games
man
lp
mail
news
...
backup
list
irc
gnats
nobody
libuuid
Debian-exim
user
sshd
student
10:50:17
#sed 's/.*://' /etc/passwd
/bin/bash
/bin/sh
/bin/sh
/bin/sh
/bin/sync
/bin/sh
/bin/sh
/bin/sh
/bin/sh
/bin/sh
...
/bin/sh
/bin/sh
/bin/sh
/bin/sh
/bin/sh
/bin/sh
/bin/false
/bin/bash
/usr/sbin/nologin
/bin/bash
10:52:11
#ls /etc
acpi                    default                 init.d           magic           profile         sgml
adduser.conf            deluser.conf            initramfs-tools  magic.mime      profile.d       shadow
adjtime                 dhcp                    inittab          mailcap         protocols       shadow-
aliases                 discover.conf.d         inputrc          mailcap.order   python          shells
alternatives            discover-modprobe.conf  insserv          mailname        python2.7       skel
apt                     dpkg                    insserv.conf     manpath.config  rc0.d           ssh
bash.bashrc             email-addresses         insserv.conf.d   mime.types      rc1.d           ssl
bash_completion         environment             iproute2         mke2fs.conf     rc2.d           staff-group-for-usr-local
bash_completion.d       exim4                   issue            modprobe.d      rc3.d           sysctl.conf
bindresvport.blacklist  file                    issue.net        modules         rc4.d           sysctl.d
...
console-cyrillic        group-                  ld.so.conf.d     networks        resolv.conf     udev
console-setup           grub.d                  lilalo           nsswitch.conf   rmt             ufw
cron.d                  gshadow                 locale.alias     opt             rpc             vim
cron.daily              gshadow-                locale.gen       os-release      rsyslog.conf    w3m
cron.hourly             host.conf               localtime        pam.conf        rsyslog.d       wgetrc
cron.monthly            hostname                logcheck         pam.d           screenrc        X11
crontab                 hosts                   login.defs       passwd          securetty       xml
cron.weekly             hosts.allow             logrotate.conf   passwd-         security
debconf.conf            hosts.deny              logrotate.d      perl            selinux
debian_version          init                    lynx-cur         ppp             services
10:52:16
#ln /etc/passwd /passwd

10:54:41
#ls
1.txt  3.txt   d1  f6  install  letter   passwd  student_con  unsorted  words
2.txt  backup  d2  f7  ip       newfile  proj    test         wget.txt
10:54:43
#ls /etc
acpi                    default                 init.d           magic           profile         sgml
adduser.conf            deluser.conf            initramfs-tools  magic.mime      profile.d       shadow
adjtime                 dhcp                    inittab          mailcap         protocols       shadow-
aliases                 discover.conf.d         inputrc          mailcap.order   python          shells
alternatives            discover-modprobe.conf  insserv          mailname        python2.7       skel
apt                     dpkg                    insserv.conf     manpath.config  rc0.d           ssh
bash.bashrc             email-addresses         insserv.conf.d   mime.types      rc1.d           ssl
bash_completion         environment             iproute2         mke2fs.conf     rc2.d           staff-group-for-usr-local
bash_completion.d       exim4                   issue            modprobe.d      rc3.d           sysctl.conf
bindresvport.blacklist  file                    issue.net        modules         rc4.d           sysctl.d
...
console-cyrillic        group-                  ld.so.conf.d     networks        resolv.conf     udev
console-setup           grub.d                  lilalo           nsswitch.conf   rmt             ufw
cron.d                  gshadow                 locale.alias     opt             rpc             vim
cron.daily              gshadow-                locale.gen       os-release      rsyslog.conf    w3m
cron.hourly             host.conf               localtime        pam.conf        rsyslog.d       wgetrc
cron.monthly            hostname                logcheck         pam.d           screenrc        X11
crontab                 hosts                   login.defs       passwd          securetty       xml
cron.weekly             hosts.allow             logrotate.conf   passwd-         security
debconf.conf            hosts.deny              logrotate.d      perl            selinux
debian_version          init                    lynx-cur         ppp             services
10:54:49
#ls
1.txt  3.txt   d1  f6  install  letter   passwd  student_con  unsorted  words
2.txt  backup  d2  f7  ip       newfile  proj    test         wget.txt
10:55:15
#sed 's/[^a]//g' /etc/passwd | wc -c
67
10:57:17
#sed 's/[^:]//g' /etc/passwd | wc -c
161
10:57:22
#sed 's/[^/]//g' /etc/passwd | wc -c
119
10:57:42
#sed 's/[! ]/-/g' /etc/passwd
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/bin/sh
bin:x:2:2:bin:/bin:/bin/sh
sys:x:3:3:sys:/dev:/bin/sh
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/bin/sh
man:x:6:12:man:/var/cache/man:/bin/sh
lp:x:7:7:lp:/var/spool/lpd:/bin/sh
mail:x:8:8:mail:/var/mail:/bin/sh
news:x:9:9:news:/var/spool/news:/bin/sh
...
backup:x:34:34:backup:/var/backups:/bin/sh
list:x:38:38:Mailing-List-Manager:/var/list:/bin/sh
irc:x:39:39:ircd:/var/run/ircd:/bin/sh
gnats:x:41:41:Gnats-Bug-Reporting-System-(admin):/var/lib/gnats:/bin/sh
nobody:x:65534:65534:nobody:/nonexistent:/bin/sh
libuuid:x:100:101::/var/lib/libuuid:/bin/sh
Debian-exim:x:101:103::/var/spool/exim4:/bin/false
user:x:1000:1000:user,,,:/home/user:/bin/bash
sshd:x:102:65534::/var/run/sshd:/usr/sbin/nologin
student:x:1001:1001::/home/student:/bin/bash
10:57:57
#sed 's/[/]/! /g' /etc/passwd
root:x:0:0:root:! root:! bin! bash
daemon:x:1:1:daemon:! usr! sbin:! bin! sh
bin:x:2:2:bin:! bin:! bin! sh
sys:x:3:3:sys:! dev:! bin! sh
sync:x:4:65534:sync:! bin:! bin! sync
games:x:5:60:games:! usr! games:! bin! sh
man:x:6:12:man:! var! cache! man:! bin! sh
lp:x:7:7:lp:! var! spool! lpd:! bin! sh
mail:x:8:8:mail:! var! mail:! bin! sh
news:x:9:9:news:! var! spool! news:! bin! sh
...
backup:x:34:34:backup:! var! backups:! bin! sh
list:x:38:38:Mailing List Manager:! var! list:! bin! sh
irc:x:39:39:ircd:! var! run! ircd:! bin! sh
gnats:x:41:41:Gnats Bug-Reporting System (admin):! var! lib! gnats:! bin! sh
nobody:x:65534:65534:nobody:! nonexistent:! bin! sh
libuuid:x:100:101::! var! lib! libuuid:! bin! sh
Debian-exim:x:101:103::! var! spool! exim4:! bin! false
user:x:1000:1000:user,,,:! home! user:! bin! bash
sshd:x:102:65534::! var! run! sshd:! usr! sbin! nologin
student:x:1001:1001::! home! student:! bin! bash
10:58:14
#sed 's/[/]/\t/g' /etc/passwd
root:x:0:0:root:        root:   bin     bash
daemon:x:1:1:daemon:    usr     sbin:   bin     sh
bin:x:2:2:bin:  bin:    bin     sh
sys:x:3:3:sys:  dev:    bin     sh
sync:x:4:65534:sync:    bin:    bin     sync
games:x:5:60:games:     usr     games:  bin     sh
man:x:6:12:man: var     cache   man:    bin     sh
lp:x:7:7:lp:    var     spool   lpd:    bin     sh
mail:x:8:8:mail:        var     mail:   bin     sh
news:x:9:9:news:        var     spool   news:   bin     sh
...
backup:x:34:34:backup:  var     backups:        bin     sh
list:x:38:38:Mailing List Manager:      var     list:   bin     sh
irc:x:39:39:ircd:       var     run     ircd:   bin     sh
gnats:x:41:41:Gnats Bug-Reporting System (admin):       var     lib     gnats:  bin     sh
nobody:x:65534:65534:nobody:    nonexistent:    bin     sh
libuuid:x:100:101::     var     lib     libuuid:        bin     sh
Debian-exim:x:101:103:: var     spool   exim4:  bin     false
user:x:1000:1000:user,,,:       home    user:   bin     bash
sshd:x:102:65534::      var     run     sshd:   usr     sbin    nologin
student:x:1001:1001::   home    student:        bin     bash
10:59:43
#sed 's/[:|/]/\t/g' /etc/passwd
root    x       0       0       root            root            bin     bash
daemon  x       1       1       daemon          usr     sbin            bin     sh
bin     x       2       2       bin             bin             bin     sh
sys     x       3       3       sys             dev             bin     sh
sync    x       4       65534   sync            bin             bin     sync
games   x       5       60      games           usr     games           bin     sh
man     x       6       12      man             var     cache   man             bin     sh
lp      x       7       7       lp              var     spool   lpd             bin     sh
mail    x       8       8       mail            var     mail            bin     sh
news    x       9       9       news            var     spool   news            bin     sh
...
backup  x       34      34      backup          var     backups         bin     sh
list    x       38      38      Mailing List Manager            var     list            bin     sh
irc     x       39      39      ircd            var     run     ircd            bin     sh
gnats   x       41      41      Gnats Bug-Reporting System (admin)              var     lib     gnats           bin     sh
nobody  x       65534   65534   nobody          nonexistent             bin     sh
libuuid x       100     101                     var     lib     libuuid         bin     sh
Debian-exim     x       101     103                     var     spool   exim4           bin     false
user    x       1000    1000    user,,,         home    user            bin     bash
sshd    x       102     65534                   var     run     sshd            usr     sbin    nologin
student x       1001    1001                    home    student         bin     bash
11:00:06
#sed 's/[:|/]/\t/g' /etc/passwd | tr -c [[:punct:]]
tr: пропущен операнд после «[[:punct:]]»
При преобразовании необходимо задать две строки.
Попробуйте «tr --help» для получения более подробного описания.
11:00:33
#sed 's/[:|/]/\t/g' /etc/passwd | tr -c [:punct:]
tr: пропущен операнд после «[:punct:]»
При преобразовании необходимо задать две строки.
Попробуйте «tr --help» для получения более подробного описания.
11:00:39
#sed 's/[:|/]/\t/g' /etc/passwd | tr -d [:punct:]
root    x       0       0       root            root            bin     bash
daemon  x       1       1       daemon          usr     sbin            bin     sh
bin     x       2       2       bin             bin             bin     sh
sys     x       3       3       sys             dev             bin     sh
sync    x       4       65534   sync            bin             bin     sync
games   x       5       60      games           usr     games           bin     sh
man     x       6       12      man             var     cache   man             bin     sh
lp      x       7       7       lp              var     spool   lpd             bin     sh
mail    x       8       8       mail            var     mail            bin     sh
news    x       9       9       news            var     spool   news            bin     sh
...
backup  x       34      34      backup          var     backups         bin     sh
list    x       38      38      Mailing List Manager            var     list            bin     sh
irc     x       39      39      ircd            var     run     ircd            bin     sh
gnats   x       41      41      Gnats BugReporting System admin         var     lib     gnats           bin     sh
nobody  x       65534   65534   nobody          nonexistent             bin     sh
libuuid x       100     101                     var     lib     libuuid         bin     sh
Debianexim      x       101     103                     var     spool   exim4           bin     false
user    x       1000    1000    user            home    user            bin     bash
sshd    x       102     65534                   var     run     sshd            usr     sbin    nologin
student x       1001    1001                    home    student         bin     bash
11:01:00
#sed 's/[/]/\t/g' /etc/passwd | tr -d [:punct:]
rootx00root     root    bin     bash
daemonx11daemon usr     sbin    bin     sh
binx22bin       bin     bin     sh
sysx33sys       dev     bin     sh
syncx465534sync bin     bin     sync
gamesx560games  usr     games   bin     sh
manx612man      var     cache   man     bin     sh
lpx77lp var     spool   lpd     bin     sh
mailx88mail     var     mail    bin     sh
newsx99news     var     spool   news    bin     sh
...
backupx3434backup       var     backups bin     sh
listx3838Mailing List Manager   var     list    bin     sh
ircx3939ircd    var     run     ircd    bin     sh
gnatsx4141Gnats BugReporting System admin       var     lib     gnats   bin     sh
nobodyx6553465534nobody nonexistent     bin     sh
libuuidx100101  var     lib     libuuid bin     sh
Debianeximx101103       var     spool   exim4   bin     false
userx10001000user       home    user    bin     bash
sshdx10265534   var     run     sshd    usr     sbin    nologin
studentx10011001        home    student bin     bash
11:01:28
#sed 's/[:|/]/\t/g' /etc/passwd | tr -d [:punct:]
root    x       0       0       root            root            bin     bash
daemon  x       1       1       daemon          usr     sbin            bin     sh
bin     x       2       2       bin             bin             bin     sh
sys     x       3       3       sys             dev             bin     sh
sync    x       4       65534   sync            bin             bin     sync
games   x       5       60      games           usr     games           bin     sh
man     x       6       12      man             var     cache   man             bin     sh
lp      x       7       7       lp              var     spool   lpd             bin     sh
mail    x       8       8       mail            var     mail            bin     sh
news    x       9       9       news            var     spool   news            bin     sh
...
backup  x       34      34      backup          var     backups         bin     sh
list    x       38      38      Mailing List Manager            var     list            bin     sh
irc     x       39      39      ircd            var     run     ircd            bin     sh
gnats   x       41      41      Gnats BugReporting System admin         var     lib     gnats           bin     sh
nobody  x       65534   65534   nobody          nonexistent             bin     sh
libuuid x       100     101                     var     lib     libuuid         bin     sh
Debianexim      x       101     103                     var     spool   exim4           bin     false
user    x       1000    1000    user            home    user            bin     bash
sshd    x       102     65534                   var     run     sshd            usr     sbin    nologin
student x       1001    1001                    home    student         bin     bash
11:01:41
#sed 's/[bin]/`1.txt`/g' /etc/passwd | tr -d [:punct:]
rootx00rootroot1txt1txt1txt1txtash
daemo1txtx11daemo1txtusrs1txt1txt1txt1txt1txt1txtsh
1txt1txt1txtx221txt1txt1txt1txt1txt1txt1txt1txt1txtsh
sysx33sysdev1txt1txt1txtsh
sy1txtcx465534sy1txtc1txt1txt1txt1txt1txt1txtsy1txtc
gamesx560gamesusrgames1txt1txt1txtsh
ma1txtx612ma1txtvarcachema1txt1txt1txt1txtsh
lpx77lpvarspoollpd1txt1txt1txtsh
ma1txtlx88ma1txtlvarma1txtl1txt1txt1txtsh
1txtewsx991txtewsvarspool1txtews1txt1txt1txtsh
...
1txtackupx34341txtackupvar1txtackups1txt1txt1txtsh
l1txtstx3838Ma1txtl1txt1txtg L1txtst Ma1txtagervarl1txtst1txt1txt1txtsh
1txtrcx39391txtrcdvarru1txt1txtrcd1txt1txt1txtsh
g1txtatsx4141G1txtats BugReport1txt1txtg System adm1txt1txtvarl1txt1txtg1txtats1txt1txt1txtsh
1txto1txtodyx65534655341txto1txtody1txto1txtex1txtste1txtt1txt1txt1txtsh
l1txt1txtuu1txtdx100101varl1txt1txtl1txt1txtuu1txtd1txt1txt1txtsh
De1txt1txta1txtex1txtmx101103varspoolex1txtm41txt1txt1txtfalse
userx10001000userhomeuser1txt1txt1txt1txtash
sshdx10265534varru1txtsshdusrs1txt1txt1txt1txtolog1txt1txt
stude1txttx10011001homestude1txtt1txt1txt1txt1txtash
11:03:21
#sed 's/'bin'/`1.txt`/g' /etc/passwd | tr -d [:punct:]
rootx00rootroot1txtbash
daemonx11daemonusrs1txt1txtsh
1txtx221txt1txt1txtsh
sysx33sysdev1txtsh
syncx465534sync1txt1txtsync
gamesx560gamesusrgames1txtsh
manx612manvarcacheman1txtsh
lpx77lpvarspoollpd1txtsh
mailx88mailvarmail1txtsh
newsx99newsvarspoolnews1txtsh
...
backupx3434backupvarbackups1txtsh
listx3838Mailing List Managervarlist1txtsh
ircx3939ircdvarrunircd1txtsh
gnatsx4141Gnats BugReporting System adminvarlibgnats1txtsh
nobodyx6553465534nobodynonexistent1txtsh
libuuidx100101varliblibuuid1txtsh
Debianeximx101103varspoolexim41txtfalse
userx10001000userhomeuser1txtbash
sshdx10265534varrunsshdusrs1txtnologin
studentx10011001homestudent1txtbash
11:05:24
#cat passwd | tr -d '^$'
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/bin/sh
bin:x:2:2:bin:/bin:/bin/sh
sys:x:3:3:sys:/dev:/bin/sh
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/bin/sh
man:x:6:12:man:/var/cache/man:/bin/sh
lp:x:7:7:lp:/var/spool/lpd:/bin/sh
mail:x:8:8:mail:/var/mail:/bin/sh
news:x:9:9:news:/var/spool/news:/bin/sh
...
backup:x:34:34:backup:/var/backups:/bin/sh
list:x:38:38:Mailing List Manager:/var/list:/bin/sh
irc:x:39:39:ircd:/var/run/ircd:/bin/sh
gnats:x:41:41:Gnats Bug-Reporting System (admin):/var/lib/gnats:/bin/sh
nobody:x:65534:65534:nobody:/nonexistent:/bin/sh
libuuid:x:100:101::/var/lib/libuuid:/bin/sh
Debian-exim:x:101:103::/var/spool/exim4:/bin/false
user:x:1000:1000:user,,,:/home/user:/bin/bash
sshd:x:102:65534::/var/run/sshd:/usr/sbin/nologin
student:x:1001:1001::/home/student:/bin/bash
прошло 13 минут
11:18:34
#cat passwd | tr -d '\n'

11:18:58
#cat passwd | tr -d '\n' | sed 's/[:|/]/\t/g'

11:20:04
#cat passwd | tr -cd 'a'

11:21:50
#cat passwd | tr -cd 'a'

11:21:56
#cat passwd | tr -cd 'a'

11:21:58
#cat passwd | tr -cd 'a'

11:22:00
#cat passwd | tr -cd 'a'

11:22:02
#cat passwd | tr -cd 'a'

11:22:03
#cat passwd | tr -cd 'a'

11:22:06
#cat passwd | tr -cd 'a'

11:22:38
#cat passwd
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/bin/sh
bin:x:2:2:bin:/bin:/bin/sh
sys:x:3:3:sys:/dev:/bin/sh
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/bin/sh
man:x:6:12:man:/var/cache/man:/bin/sh
lp:x:7:7:lp:/var/spool/lpd:/bin/sh
mail:x:8:8:mail:/var/mail:/bin/sh
news:x:9:9:news:/var/spool/news:/bin/sh
...
backup:x:34:34:backup:/var/backups:/bin/sh
list:x:38:38:Mailing List Manager:/var/list:/bin/sh
irc:x:39:39:ircd:/var/run/ircd:/bin/sh
gnats:x:41:41:Gnats Bug-Reporting System (admin):/var/lib/gnats:/bin/sh
nobody:x:65534:65534:nobody:/nonexistent:/bin/sh
libuuid:x:100:101::/var/lib/libuuid:/bin/sh
Debian-exim:x:101:103::/var/spool/exim4:/bin/false
user:x:1000:1000:user,,,:/home/user:/bin/bash
sshd:x:102:65534::/var/run/sshd:/usr/sbin/nologin
student:x:1001:1001::/home/student:/bin/bash
11:22:44
#cat passwd | tr -dc a

11:22:57
#cat passwd
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/bin/sh
bin:x:2:2:bin:/bin:/bin/sh
sys:x:3:3:sys:/dev:/bin/sh
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/bin/sh
man:x:6:12:man:/var/cache/man:/bin/sh
lp:x:7:7:lp:/var/spool/lpd:/bin/sh
mail:x:8:8:mail:/var/mail:/bin/sh
news:x:9:9:news:/var/spool/news:/bin/sh
...
backup:x:34:34:backup:/var/backups:/bin/sh
list:x:38:38:Mailing List Manager:/var/list:/bin/sh
irc:x:39:39:ircd:/var/run/ircd:/bin/sh
gnats:x:41:41:Gnats Bug-Reporting System (admin):/var/lib/gnats:/bin/sh
nobody:x:65534:65534:nobody:/nonexistent:/bin/sh
libuuid:x:100:101::/var/lib/libuuid:/bin/sh
Debian-exim:x:101:103::/var/spool/exim4:/bin/false
user:x:1000:1000:user,,,:/home/user:/bin/bash
sshd:x:102:65534::/var/run/sshd:/usr/sbin/nologin
student:x:1001:1001::/home/student:/bin/bash
11:23:03
#cat passwd | tr
tr: пропущен операнд
Попробуйте «tr --help» для получения более подробного описания.
11:23:13
#cat passwd | tr -cd a

11:23:20
#cat passwd | tr -cd a

11:23:23
#cat passwd | tr -cd a

11:23:26
#cat passwd | tr -cd a

11:23:27
#cat passwd | tr a b
root:x:0:0:root:/root:/bin/bbsh
dbemon:x:1:1:dbemon:/usr/sbin:/bin/sh
bin:x:2:2:bin:/bin:/bin/sh
sys:x:3:3:sys:/dev:/bin/sh
sync:x:4:65534:sync:/bin:/bin/sync
gbmes:x:5:60:gbmes:/usr/gbmes:/bin/sh
mbn:x:6:12:mbn:/vbr/cbche/mbn:/bin/sh
lp:x:7:7:lp:/vbr/spool/lpd:/bin/sh
mbil:x:8:8:mbil:/vbr/mbil:/bin/sh
news:x:9:9:news:/vbr/spool/news:/bin/sh
...
bbckup:x:34:34:bbckup:/vbr/bbckups:/bin/sh
list:x:38:38:Mbiling List Mbnbger:/vbr/list:/bin/sh
irc:x:39:39:ircd:/vbr/run/ircd:/bin/sh
gnbts:x:41:41:Gnbts Bug-Reporting System (bdmin):/vbr/lib/gnbts:/bin/sh
nobody:x:65534:65534:nobody:/nonexistent:/bin/sh
libuuid:x:100:101::/vbr/lib/libuuid:/bin/sh
Debibn-exim:x:101:103::/vbr/spool/exim4:/bin/fblse
user:x:1000:1000:user,,,:/home/user:/bin/bbsh
sshd:x:102:65534::/vbr/run/sshd:/usr/sbin/nologin
student:x:1001:1001::/home/student:/bin/bbsh
11:23:35
#cat passwd | tr -c -d a

11:23:48
#cat passwd | tr -c -d 'a'

11:23:52
#cat passwd | tr -c -d :

11:24:01
#cat passwd | tr -c -d \a