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Commands using cat from sorted by
Terminal - Commands using cat - 436 results
cat /var/log/httpd/access_log | grep q= | awk '{print $11}' | awk -F 'q=' '{print $2}' | sed 's/+/ /g;s/%22/"/g;s/q=//' | cut -d "&" -f 1 | mail youremail@isp.com -s "[your-site] search strings for `date`"
2009-11-22 03:03:06
User: isma
Functions: awk cat grep sed strings
-2

It's not a big line, and it *may not* work for everybody, I guess it depends on the detail of access_log configuration in your httpd.conf. I use it as a prerotate command for logrotate in httpd section so it executes before access_log rotation, everyday at midnight.

cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot
2009-11-20 14:53:26
User: taliver
Functions: awk cat head printf sort tr uniq
5

Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files.

pdftk 1.pdf 2.pdf 3.pdf cat output 123.pdf
cat /dev/hda > ~/hda.iso
cat /path/to/some/file.txt | tee /dev/pts/0 | wc -l
2009-11-07 22:24:28
User: atoponce
Functions: cat tee wc
Tags: tee
2

This is a cool trick to view the contents of the file on /dev/pts/0 (or whatever terminal you're using), and also send the contents of that file to another program by way of an unnamed pipe. All the while, you've not bothered saving any extra data to disk, like you might be tempted to do with sed or grep to filter output.

exec 3<>/dev/tcp/whatismyip.com/80; echo -e "GET /automation/n09230945.asp HTTP/1.0\r\nHost: whatismyip.com\r\n" >&3; a=( $(cat <&3) ); echo ${a[${#a[*]}-1]};
cat > list -
2009-10-29 20:20:11
Functions: cat
3

Quick write some notes to a file with cat. Ctrl+C when you have finish.

TIMEUNIT=$( cat a | grep -n "timescale" | awk -F ":" '{ print $1 } ' )
teste.txt < cut -d : -f 1,5 /etc/passwd | tr : \\t | tr a-z A-Z | cat teste.txt
cat private-file | gpg2 --encrypt --armor --recipient "Disposable Key" | mailx -s "Email Subject" user@email.com
2009-10-19 20:38:37
User: slashdot
Functions: cat mailx
2

This is a quick and easy way of encrypting files in a datastream, without ever really creating an output file from gpg. Useful with cron also, when file(s) have to be sent based on a set schedule.

for f in *.html; do head -n -1 $f > temp; cat temp > $f; rm temp; done
2009-10-12 12:49:18
User: Sunng
Functions: cat head rm
-1

Some malicious program appends a iframe or script tag to you web pages on some server, use this command to clean them in batch.

cat file.txt | while read line; do printf "%7.2f -> %7.2f\n" $line; done
cat ~/SortedFile.txt | perl -wnl -e '@f=<>; END{ foreach $i (reverse 0 .. $#f) { $r=int rand ($i+1); @f[$i, $r]=@f[$r,$i] unless ($i==$r); } chomp @f; foreach $line (@f){ print $line; }}'
2009-09-24 15:42:43
User: drewk
Functions: cat perl
0

The sort utility is well used, but sometimes you want a little chaos. This will randomize the lines of a text file.

BTW, on OS X there is no

| sort -R

option! There is also no

| shuf

These are only in the newer GNU core...

This is also faster than the alternate of:

| awk 'BEGIN { srand() } { print rand() "\t" $0 }' | sort -n | cut -f2-
host A: cat /proc/dev/ttyS0 host B: echo hello > /dev/ttyS0
2009-09-24 13:22:23
User: flart
Functions: cat echo host
2

If the connection works you should see a "hello" on host A. If not: check your cabeling etc :-)

cat -n file or cat -b file
2009-09-24 12:18:40
User: eastwind
Functions: cat file
0

cat -n file : number all line

cat -b file : number only non empty line

see man cat

cat filename | uuencode filename | mail -s "Email subject" user@example.com
2009-09-21 04:13:50
User: amaymon
Functions: cat mail uuencode
Tags: cat mail
0

uuencode the file to appear as an attachment

cat filename | mail -s "Email subject" user@example.com
2009-09-20 01:38:23
Functions: cat mail
Tags: cat mail
2

This just reads in a local file and sends it via email. Works with text or binary. *Requires* local mail server.

cat *.sql | mysql <db_name>
cat /var/lib/dpkg/info/*.list > /tmp/listin ; ls /proc/*/exe |xargs -l readlink | grep -xvFf /tmp/listin; rm /tmp/listin
2009-09-09 18:09:14
User: kamathln
Functions: cat grep ls readlink rm xargs
Tags: Debian find dpkg
11

This helped me find a botnet that had made into my system. Of course, this is not a foolproof or guarantied way to find all of them or even most of them. But it helped me find it.

cat testfile | hexdump -C
echo capitalize | { dd bs=1 count=1 conv=ucase 2> /dev/null; cat ;}
cat /etc/passwd | openssl aes-256-cbc -a -e -pass pass:password | netcat -l -p 8080
2009-09-04 20:04:24
User: flip387
Functions: cat
10

Using OpenSSL we can encrypt any input we wish and then use Netcat to create a socket which can be connected to from an externally source (even using a Web Browser)

vimdiff <(svn cat "$1") "$1"
2009-09-04 18:41:40
User: plasticboy
Functions: cat
Tags: svn vim diff color
2

This will diff your local version of the file with the latest version in svn. I put this in a shell function like so:

svd() { vimdiff <(svn cat "$1") "$1"; }
cat /service/solr/log/main/current | tai64nlocal | grep "\(`date '+%F %H'`\|`date '+%F %H %M' | awk '{print $1" 0"$2-1":"$3}'`\)" | grep QTime | awk '{print $NF}' | awk -F\= '{ s += $2} END {print s/NR}'
cat nicescript |ssh middlehost "cat | ssh -a root@securehost 'cat > nicescript'"
2009-08-25 08:11:12
User: syladmin
Functions: cat ssh
Tags: ssh scp
4

middlehost allows ssh access from where you are but not securehost.

Use nice ssh piping to simulate scp through A => B => C

setting up the shell function if left as an exercise for the reader. ;-)

Agent forwarding should avoid password typing.