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Commands using cat from sorted by
Terminal - Commands using cat - 431 results
sudo cat /usr/share/icons/*/*/* > /dev/dsp
2009-08-06 03:12:27
User: 12345678
Functions: cat sudo

Plays the sound of the file, should sound like *some* kind of music, most files sound like static but some are really cool.


sudo cat /dev/sda > /dev/dsp sudo cat /dev/sda5 | aplay

Check out http://bbs.archlinux.org/viewtopic.php?id=70937 for more variations!

semi-dupe--like http://www.commandlinefu.com/commands/view/985/generate-white-noise but with different syntax and program.

cat /etc/debian_version
2009-08-05 14:47:05
User: caiosba
Functions: cat

Easy way to find out what Debian version your machine is running

cat file-that-failed-to-download.zip | curl -C - http://www.somewhere.com/file-I-want-to-download.zip >successfully-downloaded.zip
2009-08-05 13:33:06
Functions: cat

If you are downloading a big file (or even a small one) and the connection breaks or times out, use this command in order to RESUME the download where it failed, instead of having to start downloading from the beginning. This is a real win for downloading debian ISO images over a buggy DSL modem.

Take the partially downloaded file and cat it into the STDIN of curl, as shown. Then use the "-C -" option followed by the URL of the file you were originally downloading.

cat frame/*.mpeg | ffmpeg -i $ID.mp3 -i - -f dvd -y track/$ID.mpg 2>/dev/null
2009-08-04 06:31:50
User: pamirian
Functions: cat

This is an extract from a larger script which formats the video for DVD. The videos I use have no audio track so I need to add one. Tweak as you like...

find . -type f -name "*.c" -exec cat {} \; | wc -l
2009-07-30 10:06:51
User: foremire
Functions: cat find wc

use find to grep all .c files from the target directory, cat them into one stream, then piped to wc to count the lines

cat file | tee >> file
2009-07-30 07:34:03
User: GeckoDH
Functions: cat file tee

The command `cat file >> file` failes with the following error message:

cat: file: input file is output file

`tee` is a nice workaround without using any temporary files.

cat /proc/net/ip_conntrack | grep ESTABLISHED | grep -c -v ^#
for file in *.001; do NAME=`echo $file | cut -d. -f1,2`; cat "$NAME."[0-9][0-9][0-9] > "$NAME"; done
2009-07-29 10:04:26
User: jaymzcd
Functions: cat cut file

If you use newsgroups then you'll have come across split files before. Joining together a whole batch of them can be a pain so this will do the whole folder in one.

buffer () { tty -s && return; tmp=$(mktemp); cat > "${tmp}"; if [ -n "$1" ] && ( ( [ -f "$1" ] && [ -w "$1" ] ) || ( ! [ -a "$1" ] && [ -w "$(dirname "$1")" ] ) ); then mv -f "${tmp}" "$1"; else echo "Can't write in \"$1\""; rm -f "${tmp}"; fi }
2009-07-27 20:21:15
User: Josay
Functions: cat echo mv rm tty
Tags: redirection

A common mistake in Bash is to write command-line where there's command a reading a file and whose result is redirected to that file.

It can be easily avoided because of :

1) warnings "-bash: file.txt: cannot overwrite existing file"

2) options (often "-i") that let the command directly modify the file

but I like to have that small function that does the trick by waiting for the first command to end before trying to write into the file.

Lots of things could probably done in a better way, if you know one...

cat 1.mp3 2.mp3 > combined.mp3
2009-07-27 18:39:44
User: scottix
Functions: cat

This just combines multiple mp3's into one mp3 file. Basically it is a easy join for mp3's

man -P cat ls > man_ls.txt
2009-07-27 13:09:24
User: alvinx
Functions: cat ls man

Output manpage as plaintext using cat as pager: man -P cat commandname

And redirect its stdout into a file: man -P cat commandname > textfile.txt

Example: man -P cat ls > man_ls.txt

cat /var/log/secure.log | awk '{print substr($0,0,12)}' | uniq -c | sort -nr | awk '{printf("\n%s ",$0) ; for (i = 0; i<$1 ; i++) {printf("*")};}'
2009-07-24 07:20:06
User: knassery
Functions: awk cat sort uniq

Busiest seconds:

cat /var/log/secure.log | awk '{print substr($0,0,15)}' | uniq -c | sort -nr | awk '{printf("\n%s ",$0) ; for (i = 0; i<$1 ; i++) {printf("*")};}'
cat `whereis mysqlbug | awk '{print $2}'` | grep 'CONFIGURE_LINE='
find . -name '*.html' -print0| xargs -0 -L1 cat |sed "s/[\"\<\>' \t\(\);]/\n/g" |grep "http://" |sort -u
2009-07-14 07:00:15
User: jamespitt
Functions: cat find grep sed sort xargs

Just a handy way to get all the unique links from inside all the html files inside a directory. Can be handy on scripts etc.

cat /dev/urandom|awk 'BEGIN{"tput cuu1" | getline CursorUp; "tput clear" | getline Clear; printf Clear}{num+=1;printf CursorUp; print num}'
2009-07-13 07:30:51
User: axelabs
Functions: awk cat printf
Tags: nawk awk clear tput

awk can clear the screen while displaying output. This is a handy way of seeing how many lines a tail -f has hit or see how many files find has found. On solaris, you may have to use 'nawk' and your machine needs 'tput'

infile=$1 for i in $(cat $infile) do echo $i | tr "," "\n" | sort -n | tr "\n" "," | sed "s/,$//" echo done
2009-07-12 21:23:37
User: iframe
Functions: cat echo sed sort tr
Tags: cat bash sort sed tr

Save the script as: sort_file

Usage: sort_file < sort_me.csv > out_file.csv

This script was originally posted by Admiral Beotch in LinuxQuestions.org on the Linux-Software forum.

I modified this script to make it more portable.

cat /dev/clipboard; $(somecommand) > /dev/clipboard
2009-07-10 18:48:21
User: sud0er
Functions: cat
Tags: windows cygwin

I spent a bunch of time yesterday looking for the xsel package in Cygwin- turns out you can use the /dev/clipboard device to do the same thing.

cat <<.>> somefilename
2009-07-10 17:45:42
User: tomlouie
Functions: cat
Tags: text

If you just want to write or append some text to a file without having to run a text editor, run this command. After running the command, start typing away. To exit, type . on a line by itself.

Replacing the >> with a single > will let you overwrite your file.

cat large.xml | xclip
2009-07-08 16:30:07
User: copremesis
Functions: cat

avoid mouse abuse and the constant struggle of balancing scroll velocity ... not to mention that burning sensation in your upper right shoulder ....

test `uname` = Linux && lsb_release -a || ( test `uname` = SunOS && cat /etc/release || uname -rms )
2009-07-07 20:51:30
User: virtualshock
Functions: cat test uname

Found in comments section works on most Linux flavors.

cat /var/log/auth.log | logtool -o HTML > auth.html
2009-07-03 18:17:22
Functions: cat

Logtool is a nice tool that can export log file to various format, but its strength lies in the capacity of colorize logs. This command take a log as input and colorize it, then export it to an html file for a more confortable view. Logtool is part of logtool package.Tested on Debian.

cat myfile.txt | tr -d '\n'
pdftk $* cat output $merged.pdf
find . -type f -name *.ext -exec cat {} > file.txt \;
2009-06-17 11:33:14
User: realgt
Functions: cat find

Useful if you have to put together multiple files into one and they are scattered across subdirectories. For example: You need to combine all .sql files into one .sql file that would be sent to DBAs as a batch script.

You do get a warning if you create a file by the same extension as the ones your searching for.

find . -type f -name *.sql -exec cat {} > BatchFile.txt \;

mysql -uadmin -p` cat /etc/psa/.psa.shadow` -Dpsa -e"select mail_name,name,password from mail left join domains on mail.dom_id = domains.id inner join accounts where mail.account_id = accounts.id;"