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Commands using cat from sorted by
Terminal - Commands using cat - 442 results
cat index.html | sed 's|"index.html%3Ffeed=rss2"|"http://dynamic-blog.hemca.com/?feed=rss2.html"|g'
2010-11-05 20:27:21
User: strzel_a
Functions: cat sed
2

Pipe | avoid escaping occurences problems in using sed and make it easier to use

cat file.txt | sed -e /<opening tag>/d -e /<closing tag>/G | sed -e '/./{H;$!d;}' -e 'x;/<string to search>/!d;'
2010-11-04 10:31:15
User: EBAH
Functions: cat sed
2

Working with log files that contains variable length messages wrapped between open and close tags it may be useful to filter the messages upon a keyword.

This works fine with GNU sed version 4.2 or higher, so pay attention to some unix distros (solaris, hp-ux, etc.).

Linux should be ok.

ps -u $USER -lf | grep -vE "\-bash|sshd|ps|grep|PPID" > .tmpkill; if (( $(cat .tmpkill | wc -l) > 0 )); then echo "# KILL EM ALL"; cat .tmpkill; cat .tmpkill | awk '{print $4}' | xargs kill -9; else echo "# NOTHING TO KILL"; fi; cat .tmpkill; rm .tmpkill;
2010-11-04 04:16:50
User: zsugiart
Functions: awk cat echo grep kill ps rm wc xargs
0

Kills all process that belongs to the user that runs it - excluding bash, sshd (so putty/ssh session will be spared). The bit that says grep -vE "..." can be extended to include ps line patterns that you want to spare.

If no process can be found on the hitlist, it will print # NOTHING TO KILL. Otherwise, it will print # KILL EM ALL, with the cull list.

for _a in {A..Z} {a..z};do _z=\${!${_a}*};for _i in `eval echo "${_z}"`;do echo -e "$_i: ${!_i}";done;done|cat -Tsv
2

This uses some tricks I found while reading the bash man page to enumerate and display all the current environment variables, including those not listed by the 'env' command which according to the bash docs are more for internal use by BASH. The main trick is the way bash will list all environment variable names when performing expansion on ${!A*}. Then the eval builtin makes it work in a loop.

I created a function for this and use it instead of env. (by aliasing env).

This is the function that given any parameters lists the variables that start with it. So 'aae B' would list all env variables starting wit B. And 'aae {A..Z} {a..z}' would list all variables starting with any letter of the alphabet. And 'aae TERM' would list all variables starting with TERM.

aae(){ local __a __i __z;for __a in "$@";do __z=\${!${__a}*};for __i in `eval echo "${__z}"`;do echo -e "$__i: ${!__i}";done;done; }

And my printenv replacement is:

alias env='aae {A..Z} {a..z} "_"|sort|cat -v 2>&1 | sed "s/\\^\\[/\\\\033/g"'

From: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

cat /proc/version
cat /etc/*-release
diff <(ssh [email protected] cat /path/to/file) <(ssh [email protected] cat /path/to/file2)
cat > /dev/null
2010-10-08 14:35:25
User: GouNiNi
Functions: cat
-5

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
0

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
User: BOYPT
Functions: cat grep hexdump
38

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
1

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:

#!/bin/sh

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

)

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
5

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
0

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
7

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
5

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