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Commands using cat from sorted by
Terminal - Commands using cat - 437 results
diff <(ssh user@host1 cat /path/to/file) <(ssh user@host2 cat /path/to/file2)
cat > /dev/null
2010-10-08 14:35:25
User: GouNiNi
Functions: cat

In exemple, screen can bind keys to switch between windows. I like to use Ctrl + Arrow to move left or right window. So I bind like this in .screenrc :

bindkey ^[OD prev # Ctl-left, prev window

bindkey ^[OC next # Ctl-right, next window

cat dvd_output/Layer0/IMAGE.DAT dvd_output/Layer1/IMAGE.DAT > dvd.iso
2010-10-07 18:47:39
User: clintmiller
Functions: cat

This will you combine the DDP output of DVD Studio Pro back into a standard ISO disk image so that you can double-check the DDP output process.

export GREP_COLOR='1;32'; cat /dev/urandom | hexdump -C | grep --color=auto "ca fe"
cat /dev/urandom | hexdump -C | grep "ca fe"
2010-09-27 08:20:44
Functions: cat grep hexdump

just make some data scrolling off the terminal. wow.

cat /proc/cpuinfo
ps -a |grep cat |wc -l
pdftk input.pdf cat 1-endE output output.pdf
package=$1; list=/var/lib/dpkg/info/${package}.list; inst=$(stat "$list" -c %X); cat $list | (while read file; do if [ -f "$file" ];then acc=$(stat "$file" -c %X); if [ $inst -lt $acc ]; then echo used $file; exit 0; fi; fi; done; exit 1)
2010-09-20 18:10:19
User: pipeliner
Functions: cat echo exit read stat
Tags: apt dpkg date stat

This script compares the modification date of /var/lib/dpkg/info/${package}.list and all the files mentioned there.

It could be wrong on noatime partitions.

Here is non-oneliner:




inst=$(stat "$list" -c %X);

cat $list |


while read file; do

if [ -f "$file" ]; then

acc=$(stat "$file" -c %X);

if [ $inst -lt $acc ]; then

echo used $file

exit 0




exit 1


cat VIDEO_TS/VTS_01_[1234].VOB | nice ffmpeg -i - -s 512x384 -vcodec libtheora -acodec libvorbis ~/Videos/dvd_rip.ogg
2010-09-14 14:45:27
User: zhangweiwu
Functions: cat nice
Tags: ffmpeg dvd

To rip DVD movie to ogg format using ffmpeg, follow these steps.

1) find the vob files on the mounted video DVD in VIDEO_TS that stores the movie itself. There would be a few other VOB files that stores splash screen or special features, the vob files for the movie itself can be identified by its superior size. You can verify these vob files by playing them directly with a player (e.g. mplayer)

2) concatenate all such vob files, pipe to ffmpeg

3) calculate the video size and crop size. The ogg video size must be multiple of 16 on both width and height, this is inherit limitation of theora codec. In my case I took 512x384.

The -vcodec parameter is necessary because ffmpeg doesn't support theora by itself. -acodec is necessary otherwise ffmpeg uses flac by default.

pdftk pdfname.pdf cat 1E output outputname.pdf
while [[ COUNTER -le 10 && IFS=':' ]]; do for LINE in $(cat /tmp/list); do some_command(s) $LINE; done; COUNTER=$((COUNTER+1)); done
2010-09-01 15:09:59
User: slashdot
Functions: cat

At times I find that I need to loop through a file where each value that I need to do something with is not on a separate line, but rather separated with a ":" or a ";". In this instance, I create a loop within which I define 'IFS' to be something other than a whitespace character. In this example, I iterate through a file which only has one line, and several fields separated with ":". The counter helps me define how many times I want to repeat the loop.

pdftk first.pdf second.pdf cat output output.pdf
wget http://forums.dropbox.com && wget $(cat index.html|grep "Latest Forum Build"|cut -d"\"" -f2) && wget $(cat topic.php*|grep "Linux x86:"|cut -d"\"" -f2|sort -r|head -n1) && rm -rf ~/.dropbox* && rm index.html *.php* && tar zxvf dropbox-*.tar.gz -C ~/
cat b1.avi b2.avi b3.avi b4.avi b5.avi b6.avi b7.avi > output.avi; mencoder -forceidx -oac copy -ovc copy output.avi -o output_final.avi; rm output.avi
cat | bash
2010-08-18 13:47:46
User: glaudiston
Functions: cat

Sometimes you don't want to leave history, because of passwords use or somethink like.

I think it help.

cls(){ printf "\033c";} or, if no printf, cat > c ;<ctrl+v> <ctrl+[>c <enter><ctrl-d> c(){ cat c;} #usage: c
cat $(ls -c | grep ogg | tac ) > directory/test.ogg
tee >(cat - >&2)
2010-07-20 17:22:31
User: camocrazed
Functions: cat tee

the tee command does fine with file names, but not so much with file descriptors, such as &2 (stderr). This uses process redirection to tee to the specified descriptor.

In the sample output, it's being used to tee to stderr, which is connected with the terminal, and to wc -l, which is also outputting to the terminal. The result is the output of bash --version followed by the linecount

cat /proc/acpi/thermal_zone/THRM/temperature
2010-07-11 16:07:07
User: gunslinger_
Functions: cat
Tags: temperature

Displaying system temperature your system .

shellcode version @ http://inj3ct0r.com/exploits/12554

cat file_with_tabs.txt | perl -pe 's/\t/ /g'
2010-07-11 13:01:22
User: nikc
Functions: cat perl
Tags: cat perl replace

Replaces tabs in output with spaces. Uses perl since sed seems to work differently across platforms.

cat WAR_AND_PEACE_By_LeoTolstoi.txt | tr -cs "[:alnum:]" "\n"| tr "[:lower:]" "[:upper:]" | awk '{h[$1]++}END{for (i in h){print h[i]" "i}}'|sort -nr | cat -n | head -n 30
2010-07-05 06:39:20
User: cp
Functions: awk cat head sort tr


cat WAR_AND_PEACE_By_LeoTolstoi.txt | tr -cs "[:alnum:]" "\n"| tr "[:lower:]" "[:upper:]" | sort -S16M | uniq -c |sort -nr | cat -n | head -n 30

("sort -S1G" - Linux/GNU sort only) will also do the job but as some drawbacks (caused by space/time complexity of sorting) for bigger files...

cat my.ps | nc -q 1 hp4550.mynet.xx 9100
find /var/log/apache2 -name 'access.log*gz' -exec zcat {} \; -or -name 'access.log*' -exec cat {} \;
2010-06-19 08:35:12
User: recursiverse
Functions: cat find zcat

This command allows you to stream your log files, including gziped files, into one stream which can be piped to awk or some other command for analysis.

Note: if your version of 'find' supports it, use:

find /var/log/apache2 -name 'access.log*gz' -exec zcat {} + -or -name 'access.log*' -exec cat {} +
cat /proc/acpi/battery/*/state