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Commands using echo from sorted by
Terminal - Commands using echo - 1,221 results
echo "import this" | python
2009-08-15 09:42:36
User: loquitus
Functions: echo
0

Very very cool list of quotations and directives on pythonic programming. I love them and they are sure applicable in C++ too, and for most any programming, really.

$(while [ ! -z "$(pgrep rsync)" ]; do echo; done; echo "rsync done" | mailx user@example.com) > /dev/null &
2009-08-14 19:46:59
User: matthewbauer
Functions: echo mailx
0

This will email user@example.com a message with the body: "rsync done" when there are no processes of rsync running. This can be changed for other uses by changing $(pgrep rsync) to something else, and echo "rsync done" | mailx user@example.com to another command.

echo $PATH|awk -F: ' { for (i=1; i <= NF; i++) print $i }'
echo "<?php phpinfo(); ?>" >> /srv/www/htdocs/test.php
wget http://checkip.dyndns.org && clear && echo && echo My IP && egrep -o '([[:digit:]]{1,3}\.){3}[[:digit:]]{1,3}' index.html && echo && rm index.html
ips(){ for if in ${1:-$(ip link list|grep '^.: '|cut -d\ -f2|cut -d: -f1)};do cur=$(ifconfig $if|grep "inet addr"|sed 's/.*inet addr:\([0-9\.]*\).*/\1/g');printf '%-5s%-15s%-15s\n' $if $cur $(nc -s $cur sine.cluenet.org 128 2>/dev/null||echo $cur);done;}
2009-08-07 10:04:46
User: frozenfire
Functions: cut echo grep ifconfig link sed
-3

Gets the internal and external IP addresses of all your interfaces, or the ones given as arguments

echo "Body goes here" | mutt -s "A subject" -a /path/to/file.tar.gz recipient@example.com
2009-08-05 23:06:25
User: ketil
Functions: echo
9

This command uses mutt to send the mail. You must pipe in a body, otherwise mutt will prompt you for some stuff. If you don't have mutt, it should be dead easy to install.

echo <ctrl-v><esc>c<enter>
2009-08-05 18:32:28
User: kcm
Functions: echo
9

This works in some situations where 'reset' and the other alternatives don't.

echo linux|rev
2009-08-04 12:28:44
Functions: echo
Tags: rev
1

NAME

rev - reverse lines of a file or files

SYNOPSIS

rev [file ...]

DESCRIPTION

The rev utility copies the specified files to the standard output, reversing the order of characters in every line. If no files are specified, the standard input is read.

AVAILABILITY

The rev command is part of the util-linux-ng package and is available from ftp://ftp.kernel.org/pub/linux/utils/util-linux-ng/.

copy(){ cp -v "$1" "$2"&watch -n 1 'du -h "$1" "$2";printf "%s%%\n" $(echo `du -h "$2"|cut -dG -f1`/0.`du -h "$1"|cut -dG -f1`|bc)';}
tmpfile=$(mktemp) && echo -e 'startup_message off\nscreen -t top htop\nsplit\nfocus\nscreen -t nethogs nethogs wlan0\nsplit\nfocus\nscreen -t iotop iotop' > $tmpfile && sudo screen -c $tmpfile
2009-08-03 10:14:02
User: Patola
Functions: echo screen sudo top
18

This command starts screen with 'htop', 'nethogs' and 'iotop' in split-screen. You have to have these three commands (of course) and specify the interface for nethogs - mine is wlan0, I could have acquired the interface from the default route extending the command but this way is simpler.

htop is a wonderful top replacement with many interactive commands and configuration options. nethogs is a program which tells which processes are using the most bandwidth. iotop tells which processes are using the most I/O.

The command creates a temporary "screenrc" file which it uses for doing the triple-monitoring. You can see several examples of screenrc files here: http://www.softpanorama.org/Utilities/Screen/screenrc_examples.shtml

for a in `ls`; do echo $a && convert $a -resize <Width>x<Height> $a; done
2009-08-02 22:35:24
User: leavittx
Functions: echo
0

Resizes all images in the curent directory to x resolution.

It is better than `mogrify -resize *.jpg` because of independence from extension of image (e.g. .jpg and .JPG) (:

echo $((`eix --only-names -I | wc -l` * 100 / `eix --only-names | wc -l`))%
find . -maxdepth 2 -name "*somepattern" -print0 | xargs -0 -I "{}" echo mv "{}" /destination/path
2009-08-01 01:55:47
User: jonasrullo
Functions: echo find mv xargs
3

Only tested on Linux Ubunty Hardy. Works when file names have spaces. The "-maxdepth 2" limits the find search to the current directory and the next one deeper in this example. This was faster on my system because find was searching every directory before the current directory without the -maxdepth option. Almost as fast as locate when used as above. Must use double quotes around pattern to handle spaces in file names. -print0 is used in combination with xargs -0. Those are zeros not "O"s. For xargs, -I is used to replace the following "{}" with the incoming file-list items from find. Echo just prints to the command line what is happening with mv. mv needs "{}" again so it knows what you are moving from. Then end with the move destination. Some other versions may only require one "{}" in the move command and not after the -I, however this is what worked for me on Ubuntu 8.04. Some like to use -type f in the find command to limit the type.

echo $( du -sm /var/log/* | cut -f 1 ) | sed 's/ /+/g'
2009-07-31 21:42:53
User: flux
Functions: cut du echo sed
Tags: echo bc
2

When you've got a list of numbers each on its row, the ECHO command puts them on a simple line, separated by space. You can then substitute the spaces with an operator. Finally, pipe it to the BC program.

echo 1 > /proc/sys/kernel/sysrq; echo b > /proc/sysrq-trigger
2009-07-31 19:07:40
User: tiagocruz
Functions: echo
Tags: proc
2

Useful when you have some wrong on a server (nfs freeze/ immortal process)

no_of_files=10; counter=1; while [[ $counter -le $no_of_files ]]; do echo Creating file no $counter; dd bs=1024 count=$RANDOM skip=$RANDOM if=/dev/sda of=random-file.$counter; let "counter += 1"; done
2009-07-31 16:34:47
User: rajaseelan
Functions: dd echo file
Tags: bash dd
0

Create a bunch of random files with random binary content. Basically dd dumps randomly from your hard disk to files random-file*.

ps -o rss -C httpd | tail -n +2 | (sed 's/^/x+=/'; echo x) | bc
2009-07-31 15:15:08
Functions: echo ps sed tail
4

Display the amount of memory used by all the httpd processes. Great in case you are being Slashdoted!

echo -e "HEAD / HTTP/1.1\nHost: slashdot.org\n\n" | nc slashdot.org 80 | head -n5 | tail -1 | cut -f2 -d-
echo -e "HEAD / HTTP/1.1\nHost: slashdot.org\n\n" | nc slashdot.org 80 | egrep "Bender|Fry" | sed "s/X-//"
2009-07-30 19:15:07
Functions: echo egrep sed
5

slashdot.org webserver adds an X-Bender or X-Fry HTTP header to every response!

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
2

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...

while true ; do IFS="" read i; echo "$i"; sleep .01; done < <(tr -c "[:digit:]" " " < /dev/urandom | dd cbs=$COLUMNS conv=unblock | GREP_COLOR="1;32" grep --color "[^ ]")
2009-07-22 03:59:07
Functions: dd echo grep read sleep tr true
Tags: color
2

Same as above but slooooow it down

ran=$(head /dev/urandom | md5sum); MAC=00:07:${ran:0:2}:${ran:3:2}:${ran:5:2}:${ran:7:2}; sudo ifconfig wlan0 down hw ether $MAC; sudo ifconfig wlan0 up; echo ifconfig wlan0:0
2009-07-16 16:21:44
User: workingsmart
Functions: echo head ifconfig sudo
7

Next time you are leaching off of someone else's wifi use this command before you start your bittorrent ...for legitimate files only of course.

It creates a hexidecimal string using md5sum from the first few lines of /dev/urandom and splices it into the proper MAC address format. Then it changes your MAC and resets your wireless (wlan0:0).

diff <(echo "$a") <(echo "$b")
2009-07-15 07:26:23
User: olorin
Functions: diff echo
25

You got some results in two variables within your shell script and would like to find the differences? Changes in process lists, reworked file contents, ... . No need to write to temporary files. You can use all the diff parameters you'll need. Maybe anything like $ grep "^>"

is helpful afterwards.

for i in `rpm -qva | sort ` ; do ; echo "===== $i =====" ; rpm -qvl $i ; done > /tmp/pkgdetails
2009-07-14 20:34:55
User: tkunz
Functions: echo rpm sort
0

This will create the file /tmp/pkgdetails, which will contain a listing of all the files installed on your RPM-based system (RedHat, Fedora, CentOS, etc). Useful should the RPM system/database become corrupted to find which package installed which files.