messing with text files
test content
# test if /path/file contains SEARCH_PATTERN if grep -q SEARCH_PATTERN "/path/file"; then cat /path/file; # do something fi
paste
basically line-wise combines two files into one. (first line of two files will end up in one line)
# add 3 new test-users to system for u in jim bob joe; do useradd -m $u; done # generate list of users file echo jim >> users echo bob >> users echo joe >> users # generate password file pwgen -B 6 3 > passwords; paste users passwords; # will combine the two files jim Ethee3 joe aitaJ4 bob ooJoh9 # will combine the two files - with delimiter being a :colon: # and write the output to screen and file users_and_passwords paste -d: users passwords|tee users_and_passwords; jim:Ethee3 joe:aitaJ4 bob:ooJoh9 # you can feed that output to chpasswd to update the passwords of all 3 users (need to exist) chpasswd < users_and_passwords;
join
similar to paste – it adds lines together.
# generate teste data echo "1 England" >> country; echo "2 Germany" >> country; echo "3 Russia" >> country; echo "4 Brazil" >> country; echo "3 Moscow" >> city; echo "1 London" >> city; echo "4 SaoPaulo" >> city; echo "2 Berlin" >> city; # unfortunately you will have to sort the unsorted second list first sort -k1,1 country > country_sorted # otherwise you will get "is not sorted" join city country 1 London England 2 Berlin Germany 3 Moscow Russia 4 SaoPaulo Brazil
concatenate
cat e* >e.txt; # concatenate = combine all files starting with e... into one file e.txt cat -n e.txt; # output to screen, number lines 1999 find: ‘/etc/sudoers.d’: Keine Berechtigung 2000 find: ‘/etc/lvm/archive’: Keine Berechtigung 2001 find: ‘/etc/lvm/backup’: Keine Berechtigung 2002 find: ‘/etc/lvm/cache’: Keine Berechtigung 2003 find: ‘/etc/audisp’: Keine Berechtigung 2004 find: ‘/etc/audit’: Keine Berechtigung 2005 find: ‘/etc/polkit-1/rules.d’: Keine Berechtigung 2006 2007 find: ‘/etc/autoinstall’: Keine Berechtigung ... tac e.txt; # output file in reverse order head -n3 file; # output first 3 lines of file head -c128 /bin/cat; # output first 20 bytes of file /bin/cat reset; # reset console head -n -3 file; # output anything but the last 3 lines of file tail -n3 file; # output only last 3 lines of file tail -f file; # follow changes of file (nice for log file real time view) od /etc/passwd|head -n3; # output in octal format first 3 lines of /etc/passwd 0000000 072141 074072 031072 035065 032462 041072 072141 064143 0000020 065040 061157 020163 060544 066545 067157 027472 060566 0000040 027562 070163 067557 027554 072141 067552 071542 027472 od -txC /etc/passwd|head -n3; # output in hex format first 3 lines of /etc/passwd 0000000 61 74 3a 78 3a 32 35 3a 32 35 3a 42 61 74 63 68 0000020 20 6a 6f 62 73 20 64 61 65 6d 6f 6e 3a 2f 76 61 0000040 72 2f 73 70 6f 6f 6c 2f 61 74 6a 6f 62 73 3a 2f od -txCz /etc/passwd|head -n3; # output in hex format but also in ASCII the first 3 lines of /etc/passwd 0000000 61 74 3a 78 3a 32 35 3a 32 35 3a 42 61 74 63 68 >at:x:25:25:Batch< 0000020 20 6a 6f 62 73 20 64 61 65 6d 6f 6e 3a 2f 76 61 > jobs daemon:/va< 0000040 72 2f 73 70 6f 6f 6c 2f 61 74 6a 6f 62 73 3a 2f >r/spool/atjobs:/< \_offset \_ 20(HEX) = 32(DEC) = " " (SPACE) hexdump -o -s 446 -n 64 /etc/passwd; # similar to od but flexibler in output 00001be 061057 067151 063057 066141 062563 066412 067141 074072 00001ce 030472 035063 031066 046472 067141 060565 020154 060560 00001de 062547 020163 064566 073545 071145 027472 060566 027562 00001ee 060543 064143 027545 060555 035156 061057 067151 061057 00001fe vim tab.txt; # create new file fill with content Fritz ist heute anscheinend sehr müde deswegen wird er nicht mehr lange wach bleiben od -txCz tab.txt 0000000 46 72 69 74 7a 09 69 73 74 09 68 65 75 74 65 09 >Fritz.ist.heute.< 0000020 61 6e 73 63 68 65 69 6e 65 6e 64 09 73 65 68 72 >anscheinend.sehr< 0000040 0a 6d c3 bc 64 65 09 64 65 73 77 65 67 65 6e 09 >.m..de.deswegen.< 0000060 77 69 72 64 09 65 72 09 6e 69 63 68 74 0a 6d 65 >wird.er.nicht.me< 0000100 68 72 09 6c 61 6e 67 65 09 77 61 63 68 09 62 6c >hr.lange.wach.bl< 0000120 65 69 62 65 6e 0a >eiben.< 0000126 expand tab.txt |od -txCz; # convert tabs to spaces 0000000 46 72 69 74 7a 20 20 20 69 73 74 20 20 20 20 20 >Fritz ist < 0000020 68 65 75 74 65 20 20 20 61 6e 73 63 68 65 69 6e >heute anschein< 0000040 65 6e 64 20 20 20 20 20 73 65 68 72 0a 6d c3 bc >end sehr.m..< 0000060 64 65 20 20 20 20 64 65 73 77 65 67 65 6e 20 20 >de deswegen < 0000100 20 20 20 20 20 20 77 69 72 64 20 20 20 20 65 72 > wird er< 0000120 20 20 20 20 20 20 6e 69 63 68 74 0a 6d 65 68 72 > nicht.mehr< 0000140 20 20 20 20 6c 61 6e 67 65 20 20 20 77 61 63 68 > lange wach< 0000160 20 20 20 20 62 6c 65 69 62 65 6e 0a > bleiben.< 0000174 cat tab.txt |od -txCz 0000000 46 72 69 74 7a 09 69 73 74 09 68 65 75 74 65 09 >Fritz.ist.heute.< 0000020 61 6e 73 63 68 65 69 6e 65 6e 64 09 73 65 68 72 >anscheinend.sehr< 0000040 0a 6d c3 bc 64 65 09 64 65 73 77 65 67 65 6e 09 >.m..de.deswegen.< 0000060 77 69 72 64 09 65 72 09 6e 69 63 68 74 0a 6d 65 >wird.er.nicht.me< 0000100 68 72 09 6c 61 6e 67 65 09 77 61 63 68 09 62 6c >hr.lange.wach.bl< 0000120 65 69 62 65 6e 0a >eiben.< 0000126 expand -t 18 tab.txt; # convert tabs to spaces in this case 18 spaces Fritz ist heute anscheinend sehr müde deswegen wird er nicht mehr lange wach bleiben expand -t 18 tab.txt >x.tab; unexpand -a x.tab |od -txCz; # convert spaces to tabs 0000000 46 72 69 74 7a 09 09 20 20 69 73 74 09 09 20 20 >Fritz.. ist.. < 0000020 20 20 68 65 75 74 65 09 20 20 20 20 20 20 61 6e > heute. an< 0000040 73 63 68 65 69 6e 65 6e 64 09 73 65 68 72 0a 6d >scheinend.sehr.m< 0000060 c3 bc 64 65 09 09 20 20 64 65 73 77 65 67 65 6e >..de.. deswegen< 0000100 09 20 20 20 20 77 69 72 64 09 20 20 20 20 20 20 >. wird. < 0000120 65 72 09 09 6e 69 63 68 74 0a 6d 65 68 72 09 09 >er..nicht.mehr..< 0000140 20 20 6c 61 6e 67 65 09 09 20 20 20 20 77 61 63 > lange.. wac< 0000160 68 09 20 20 20 20 20 20 62 6c 65 69 62 65 6e 0a >h. bleiben.< 0000200 tr t T <inhalt; # replace all small t with capital T tr a-z A-Z > tab_duplicates.txt; # run this like 10 times # now this file contains a lot of duplicate lines sort tab_duplicates.txt |uniq; # uniq again filters out all duplicate lines Fritz ist heute anscheinend sehr mehr lange wach bleiben müde deswegen wird er nicht sort tab_duplicates.txt |uniq -c; # report how many duplicates of which lines are in the file (9 duplicates) 9 Fritz ist heute anscheinend sehr 9 mehr lange wach bleiben 9 müde deswegen wird er nicht ls -l >inhalt; # create a new file with the content of current directory listing # extract/cut out all chars from position 13-20 and 33-44 in each line cut -c 13-20,33-44 inhalt |tail -n +2; # tail -n +2 - do not output the first two lines user us. Apr 11:13 user us. Apr 13:45 user us. Apr 13:01 user us. Apr 13:45 user us. Apr 13:45 user us. Apr 16:34 user us. Apr 16:38 user us. Apr 16:42 # export first row of :semicolon:separated:passwd:file cut -d: -f 1 /etc/passwd >x1; # export fifth row of :semicolon:separated:passwd:file cut -d: -f 5 /etc/passwd >x5; # combine the two files line wise paste x1 x5; at Batch jobs daemon bin bin daemon Daemon ftp FTP account ftpsecure Secure FTP User games Games account gdm Gnome Display Manager daemon lp Printing daemon mail Mailer daemon ... # reformat with expand for better formatting paste x5 x1 |expand -t 35; Batch jobs daemon at bin bin Daemon daemon FTP account ftp Secure FTP User ftpsecure Games account games Gnome Display Manager daemon gdm Printing daemon lp Mailer daemon mail ... # prepare test case # create new file fill with vim j1; 1 Hans 2 Peter 3 Fritz 4 Josef 5 Dieter # create new file fill with vim j2; 1 230 2 20 3 47 4 88 5 20 paste j1 j2 |expand -t 35 1 Hans 1 230 2 Peter 2 20 3 Fritz 3 47 4 Josef 4 88 5 Dieter 5 20 # join two numbered (keys) files into one output join j1 j2; 1 Hans 230 2 Peter 20 3 Fritz 47 4 Josef 88 5 Dieter 20
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