Commands using cat (514)
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"normalize" a my.cnf file.
0cat my.cnf | sed '/^#/d' | sed '/^$/d' | sed -e 's/[ \t]\+//g' -
Multi-word parameters in my.cnf can be written with either hyphens or underscores. innodb_file_per_table is the same as innodb-file-per-table, as well as innodb_file-per_table. The script normalizes the parameter names to using underscores only, keeping from changing values (e.g. ?mysql-bin? parameter value should not change).
0cat my.sandbox.cnf | awk -F "=" 'NF < 2 {print} sub("=", "=~placeholder~=") {print}' | awk -F "=~placeholder~=" 'NF < 2 {gsub("-", "_", $0); print} NF==2 {gsub("-", "_", $1); print $1 "=" $2}' -
0cat video.avi.001 video.avi.002 video.avi.003 >> video.avi
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0pdftk input1.pdf input2.pdf cat output output.pdf
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0find src/ -name "*.java" | while read f; do echo -n "$f "; cat "$f" | tr -dc '{}'; echo; done | awk '{ print length($2), $1 }' | sort -n
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Join all sequentially named files in the directory. Use this for files split by utilities like hjsplit and similar. This command does not do/perform _any_ sanity checks before acting, except that it won't run unless there is a file that matches "*.001". - The outfile should not already exist. - There should be more than one file. (*.002 should exist as well as *.001) - The file-count should match the number in the name of the last file in the series. - None of the files should be empty. - All files should be the same size, except for the last, which should usually be smaller, but never larger than the rest. A safer altenative can be found here: http://pastebin.com/KSS0zU2F
0x=(*.001); cat "${x%.001}."* > "${x%.001}" #unsafe; does not check that all the parts are there, or that the file-sizes make sense! -
Using large wordlists is cumbersome. Using password cracking programs with rules such as Hashcat or John the ripper is much more effective. In order to do this many times we need to "clean" a wordlist removing all numbers, special characters, spaces, whitespace and other garbage. This command will covert a entire wordlist to all lowercase with no garbage.
0cat dirtyfile.txt | awk '{gsub(/[[:punct:]]/,"")}1' | tr A-Z a-z | sed 's/[0-9]*//g' | sed -e 's/ //g' | strings | tr -cs '[:alpha:]' '\ ' | sed -e 's/ /\n/g' | tr A-Z a-z | sort -u > cleanfile.txt -
Fast and excludes words with apostrophes. For ubuntu, you can use wamerican or wbritish dictionaries, installable through aptitude. Show Sample Output
0echo $(cat /usr/share/dict/words |grep -v "'"|shuf -n4) -
This version now adds a header with consecutive numbering. Show Sample Output
0cat file.csv | perl -pe 'if($. == 1) {@h = split(/;/); $i = 1 ; map { $_ = $i; $i++ } @h; print join(" ;", @h) , "\n"} ; s/(^|;);/$1 ;/g' | column -ts\; | less -S -
pub key in ./ssh/authorized_keys needed because ssh-ed ssh can't ask for the password.
0cat file.orig | ssh user1@host1 "ssh user2@host2 \"ssh user3@server3 'cat >file.dest'\"" -
with a semicolon text file map, apply multiple replace to a single file Show Sample Output
0cat table-mv.txt | perl -pe 's{([^;]+);([^;]+)}{tbl$1/tbl$2}' | perl -pe 's{(\S+)}{perl -i -pe #s/$1/g# xxx.sql}' | tr "#" "\'" | bash -
0cat /etc/passwd | grep "bash" | cut -d: -f1
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Play local mp3 file on remote machine's speakers through ssh
0cat myfile.mp3 | ssh user@remotemachine "mplayer -cache 8912 -" -
Very useful for logs
0cat /file/way/somelogforexample | grep -o "[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}" | sort -n | uniq -c | sort -n -
0date -d @$(echo $(($(date +%s)-$(cat /proc/uptime|cut -d. -f1))))
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cat without comments
0cat /etc/squid/squid.conf | grep -v '^#' | sed '/^$/d' -
Using urandom to get random data, deleting non-letters with tr and print the first $1 bytes.
0genRandomText() { cat /dev/urandom|tr -dc 'a-zA-Z'|head -c $1 } -
0PID=`ps | grep process_name | grep -v grep | head -n 1 | awk '{print $1}'`; cat /proc/$PID/smaps | grep heap -A 2
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similar to previous except this exports to a temporary file, opens that file with your default web browser, then deletes it.
0x="/tmp/auth.html";sudo cat /var/log/auth.log | logtool -o HTML >$x;xdg-open $x;rm $x -
0cat file.txt | putclip
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useful to count events in logs Show Sample Output
0cat z.log | grep Timeout | cut -d ':' -f1 | sort | uniq -c -
useful to count events in logs @see: http://www.commandlinefu.com/commands/view/10327/report-summary-of-string-occurrence-by-time-period-hour#comment Show Sample Output
0cat z.log | cut -d ':' -f1 | sort | uniq | xargs -l1 -iFF echo 'echo FF $(cat z.log | grep -e "^FF" | grep -e Timeout | wc -l )' | bash -
depends on date format locale ... Show Sample Output
0cat z.log | cut -d ':' -f1,2 | uniq -c -
optionally you can add
|cut -d' ' -f2|uniqto the end of the command line.0for a in $(cat sample.txt); do echo "$(wc -m<<<$a) $a";done|sort -n -
0for a in $(cat sample.txt); do echo "${#a} $a";done|sort -n
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