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Functions

Commands using cat from sorted by
Terminal - Commands using cat - 445 results
find /usr/include/ -name '*.[c|h]pp' -o -name '*.[ch]' -exec cat {} \;|wc -l
2011-12-01 19:58:52
User: kerim
Functions: cat find wc
-4

Count your source and header file's line numbers

For example for java change the command like this

find . -name '*.java' -exec cat {} \;|wc -l

for file in ./*; do cat "$file"; sleep 0.3
2011-11-28 20:10:57
User: DopeGhoti
Functions: cat file sleep
-2

Original submitted version would break if any filenames had whitespaces in them. The command is a Bad Idea anyhow, because you will end up `cat`ing a binary or something else specacularly bad.

for f in *; do clear; cat $f; sleep .3; done
2011-11-25 17:10:47
User: toddkaufmann
Functions: cat sleep
-2

The better alternative to #9756.

I don't think I'd ever use the original command, but this one was so bad I had to post this. Sorry.

1. $(ls) is dumb, and will give errors if you have an alias like "ls -Fs"

2. clear is better and more portable than reset state.

3. if you're interested in differences, then use diff, not cat.

while true; do cat /proc/net/dev; sleep 1; done | awk -v dc="date \"+%T\"" '/eth0/{i = $2 - oi; o = $10 - oo; oi = $2; oo = $10; dc|getline d; close(dc); if (a++) printf "%s %8.2f KiB/s in %8.2f KiB/s out\n", d, i/1024, o/1024}'
2011-11-21 05:24:44
Functions: awk cat printf sleep
Tags: awk sh
10

poorman's ifstat using just sh and awk. You must change "eth0" with your interface's name.

cat /dev/urandom | tr -dc A-Za-z0-9 | head -c 32
cat <file> > /dev/null
2011-11-12 15:45:27
User: totti
Functions: cat
Tags: ram file cache
9

Best result when file size less than half of RAM size

date -d @$(echo $(($(date +%s)-$(cat /proc/uptime|cut -d. -f1))))
nocomments () { cat $1 | egrep -v '^[[:space:]]*#|^[[:space:]]*$|^[[:space:]]*;' | sed '/<!--.*-->/d' | sed '/<!--/,/-->/d'; }
2011-11-04 12:47:39
User: RuizTapiador
Functions: cat egrep sed
Tags: sed grep comment
1

Hide comments and empty lines, included XML comments,

cat /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
cat /var/log/auth.log | grep -i "pam_unix(sshd:auth): authentication failure;" | cut -d' ' -f14,15 | cut -d= -f2 | sort | uniq
2011-10-25 04:58:09
User: JohnQUnknown
Functions: cat cut grep sort
0

This command shows a sorted list of the IP addresses from which there have been authentication errors via SSH (possible script kiddies trying to gain access to your server), it eliminates duplicates so it's easier to read, but you can remove the "uniq" command at the end, or even do a "uniq -c" to have a count of how many times each IP address shows in the log (the path to the log may vary from system to system)

cat myfile.mp3 | ssh [email protected] "mplayer -cache 8912 -"
2011-10-22 23:06:44
User: sidis405
Functions: cat ssh
0

Play local mp3 file on remote machine's speakers through ssh

cat /etc/passwd | grep "bash" | cut -d: -f1
cat .ssh/id_rsa.pub | ssh [email protected] "cat >>.ssh/authorized_keys2"
cat table-mv.txt | perl -pe 's{([^;]+);([^;]+)}{tbl$1/tbl$2}' | perl -pe 's{(\S+)}{perl -i -pe #s/$1/g# xxx.sql}' | tr "#" "\'" | bash
2011-10-05 15:55:34
User: hute37
Functions: cat perl tr
0

with a semicolon text file map, apply multiple replace to a single file

cat ~/.ssh/id_rsa.pub | ssh <REMOTE> "(cat > tmp.pubkey ; mkdir -p .ssh ; touch .ssh/authorized_keys ; sed -i.bak -e '/$(awk '{print $NF}' ~/.ssh/id_rsa.pub)/d' .ssh/authorized_keys; cat tmp.pubkey >> .ssh/authorized_keys; rm tmp.pubkey)"
2011-09-30 07:39:24
User: tamouse
Functions: cat ssh
Tags: ssh awk
4

This one is a bit more robust -- the remote machine may not have an .ssh directory, and it may not have an authorized_keys file, but if it does already, and you want to replace your ssh public key for some reason, this will work in that case as well, without duplicating the entry.

cat /dev/scd0 > ~/audio_image.iso
2011-09-24 15:29:27
User: eastwind
Functions: cat
-8

you should umount /dev/cdrom before using this cli

cat file.orig | ssh [email protected] "ssh [email protected] \"ssh [email protected] 'cat >file.dest'\""
2011-09-23 12:49:19
User: Cell
Functions: cat ssh
0

pub key in ./ssh/authorized_keys needed because ssh-ed ssh can't ask for the password.

cat file.txt | sendmail -F myname -f [email protected] [email protected]
while :; do cat file.txt | nc -l 80; done
cat x
cat /proc/PID/environ | tr '\0' '\n'
cat aaaaaa 2>&-
cat -n file.txt
cat file.csv | perl -pe 'if($. == 1) [email protected] = split(/;/); $i = 1 ; map { $_ = $i; $i++ } @h; print join(" ;", @h) , "\n"} ; s/(^|;);/$1 ;/g' | column -ts\; | less -S
echo $(cat /usr/share/dict/words |grep -v "'"|shuf -n4)
2011-08-31 12:48:14
User: d1v3rdown
Functions: cat echo grep
Tags: cat echo grep shuf
0

Fast and excludes words with apostrophes. For ubuntu, you can use wamerican or wbritish dictionaries, installable through aptitude.