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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
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Commands using echo from sorted by
Terminal - Commands using echo - 1,331 results
for i in *.png; do convert "$i" "${i%.png}.jpg" && rm "$i" && echo "$i is converted."; done
2010-01-02 16:26:13
User: auriza
Functions: echo rm

Convert all PNG images in directory to JPEG using ImageMagick, and delete the old PNG images.

echo 'Desktop SPAM!!!' | while read SPAM_OUT; do notify-send "$SPAM_OUT"; done
2009-12-31 15:38:35
User: michelsberg
Functions: echo read
Tags: notify-send

Route output to notify-send to show nice messages on the desktop, e.g. title and interpreter of the current radio stream

xlaunch(){ T=/tmp/$$;sh -c "[email protected]" >$T.1 2>$T.2;S=$?;[ $S -ne 0 ]&&{ echo -e "'[email protected]' failed with error $S\nSTDERR:\n$(cat $T.2)\nSTDOUT:\n$(cat $T.1)\n"|xmessage -file -;};rm -f $T.1 $T.2;}
2009-12-31 06:59:56
User: bhepple
Functions: echo
Tags: X

When you run an X program from a terminal you can see any errors. But when it's run from another X program (eg from a menu item, from your fluxbox 'keys' file etc) it might just die and you see nothing (except perhaps in .xsession-errors). Instead, launch it via this command and you'll see the termination status, stderr and stdout.

eg: "xlaunch firefox" or "xlaunch 'echo stdout; echo stderr >&2; false'":

'echo stdout; echo stderr >&2; false' failed with error 1





BACKUP_FILE_SIZE=`eval ls -l ${BACKUP_FILE} | awk {'print $5'}`; if [ $BACKUP_FILE_SIZE -le 20 ]; then echo "its empty"; else echo "its not empty"; fi
2009-12-29 08:34:37
User: Redrocket
Functions: awk echo ls

If you gzip an empty file it becomes 20 bytes. Some backup checks i do check to see if the file is greater than zero size (-s flag) but this is no good here. Im sure someone has a better check than me for this? No check to see if file exists before checking it's size.

b(){ echo "scale=${2:-2}; $1" | bc -l; }
2009-12-23 23:44:31
User: dadi
Functions: bc echo

terms inclosing '()' must be enclosed by "" (soft quotes)

bash variables must be referenced: b $x/$y

ugly bracket checking (balanced, fractions...)

default precision 2

DIR=. ; FSTYPE=$(df -TP ${DIR} | grep -v Type | awk '{ print $2 }') ; echo "${FSTYPE}"
2009-12-22 14:01:50
User: unixhome
Functions: awk df echo grep

Exclude 400 client hosts with NFS auto-mounted home directories.

Easily modified for inclusion in your scripts.

echo -ne "\e[32m" ; while true ; do echo -ne "\e[$(($RANDOM % 2 + 1))m" ; tr -c "[:print:]" " " < /dev/urandom | dd count=1 bs=50 2> /dev/null ; done
2009-12-19 19:05:04
User: psykotron
Functions: dd echo tr true
Tags: color

A bit different from some of the other submissions. Has bold and uses all c printable characters. Change the bs=value to speed up and increase the sizes of the bold and non-bold strings.

p() { l=$LINES; case $1 in do) shift; IFS=$'\n' _pg=( $("[email protected]") ) && _pgn=0 && p r;; r) echo "${_pg[*]:_pgn:$((l-4))}";; d) (( _pgn+=l-4 )); (( _pgn=_pgn>=${#_pg[@]}?${#_pg[@]}-l+4:_pgn )); p r;; u) (( _pgn=_pgn<=l-4?0:_pgn-$l-4 )); p r;; esac; }
2009-12-18 23:35:53
User: intuited
Functions: echo
Tags: bash pager

Manpages, command summaries, and pretty much everything else usually have the information you're most likely to want at the beginning. Seeing just the last 40 or so lines of options from a command that has 100 is not super useful, and having to scroll up each time you want to glance at something is spastic.

Run this and then do something like

p do vi --help

and you'll get the first screen(-mostly-)full of vi's usage info and options list

Then use

p d

to page down, and

p u

to page up.

To see the current page again:

p r

Also useful for situations like

p do aptitude search ~dsmorgasbord p next #p sudo aptitude -r install libwickedawesome-perl-snoochieboochies p next p sudo aptitude -r install libwickedawesome-perl-snoochieboochies snazztasticorama-dev-v0.&#8734;

where you're using readline up-arrow, HOME, END, etc., to quickly recall commented commands.

For the unaware, that option to aptitude search will bring up all of the packages whose descriptions contain the string "smorgasbord". Depending on your distro, there could potentially be hundreds of them.

getent shadow | while IFS=: read a b c; do grep -q '!' <<< "$b" && echo "$a LOCKED" || echo "$a not locked"; done
2009-12-18 15:24:19
User: sputnick
Functions: echo getent grep read
man 5 shadow

I think it's more reliable, because

passwd -S

dont show "locked" but "L" as second field on my Archlinux for a particular user.

( unixhome alternative ).

awk -F":" '{ print $1 }' /etc/passwd | while read UU ; do STATUS=$(passwd -S ${UU} | grep locked 2>/dev/null) ; if [[ ! -z ${STATUS} ]] ; then echo "Account ${UU} is locked." ; fi ; done
echo $LS_COLORS | sed 's/:/\n/g' | awk -F= '!/^$/{printf("%s \x1b[%smdemo\x1b[0m\n",$0,$2)}'
2009-12-15 01:17:46
User: bones7456
Functions: awk echo sed

This can show all ls colors, with a demo.

while [ 1 ]; do banner 'ze missiles, zey are coming! ' | while IFS="\n" read l; do echo "$l"; sleep 0.01; done; done
2009-12-14 07:40:07
User: craigds
Functions: banner echo read sleep

Displays a scrolling banner which loops until you hit Ctrl-C to terminate it.

Make sure you finish your banner message with a space so it will loop nicely.

{ echo -e "$body"; uuencode "$outfile" "$outfile"; } | mail -s "$subject" "$destaddr" ;
2009-12-10 18:08:59
User: glaudiston
Functions: echo mail uuencode
Tags: cat mail

on this way we can define the body too

time { i=0; while [ $(( i < 65535 )) -eq 1 ] ; do nc -zw2 localhost $((++i)) && echo port $i opened ; done; }
2009-12-09 17:33:47
User: glaudiston
Functions: echo time

in loop, until the last port (65535), list all opened ports on host.

in the sample I used localhost, but you can replace with any host to test.

while read str; do echo "$((++i)) - $str"; done < infile
2009-12-09 15:11:25
User: putnamhill
Functions: echo read
Tags: bash

Hi glaudiston, you can save a few chars by leaving out cat and pipe and still enjoy the added flexibility.

cat infile | while read str; do echo "$((++i)) - $str" ; done;
2009-12-09 14:05:09
User: glaudiston
Functions: cat echo read

Yep, is hard, but is a way more flexible using pipe.

alias :q='tput setaf 1; echo >&2 "this is NOT vi(m) :/"; tput sgr0'
2009-12-08 12:59:44
User: sputnick
Functions: alias echo tput
Tags: vim alias vi tput

For vi(m) users :

Add it in your ~/.bashrc

Add an "exit" @ the end if you are masochist ;)

nc -zw2 www.example.com 80 && echo open
2009-12-07 21:35:25
User: sputnick
Functions: echo
Tags: netcat nc

@putnamhill, no need if statement in that case.

&& is a AND and || is a OR

if (nc -zw2 www.example.com 80); then echo open; fi
echo <ctrl+v><ctrl+o><enter>
2009-12-07 20:02:33
User: mkobler
Functions: echo

Also works in places where reset does not.

MyIps(){ echo -e "local:\n$(ifconfig $1 | grep -oP 'inet (add?r:)?\K(\d{1,3}\.){3}\d{1,3}')\n\npublic:\n$(curl -s sputnick-area.net/ip)"; }
2009-12-06 22:52:31
User: sputnick
Functions: echo

Like the tiltle said, you can use an argument too ( the interface )

MyIps eth0

will show only the IP of this interface and the public IP

( tested with Linux )

You can add that function in ~/.bashrc, then

. ~/.bashrc

Now you are ready to call this function in all your terms...

for f in *.jar; do if jar -tf $f | grep -q javax.servlet; then echo $f; fi; done
2009-12-04 20:11:36
User: wekoch
Functions: echo grep

You could subsitute javax.servlet for any namespace you need.

command_not_found_handle() { echo 6661696c626f61742e2e2e0a | xxd -p -r; }
2009-12-03 21:33:35
Functions: echo

This will give you a friendly warning if a command doesn't exists.

echo "(Something like http://foo.com/blah_blah)" | grep -oP "\b(([\w-]+://?|www[.])[^\s()<>]+(?:\([\w\d]+\)|([^[:punct:]\s]|/)))"
sudo echo 0 > /sys/block/sdb/queue/rotational
2009-11-27 12:16:17
User: nickleus
Functions: echo sudo

if you still get a permissions error using sudo, then nano the file:

sudo nano -w /sys/block/sdb/queue/rotational

and change 1 to 0

this thread:


says that this will "help the block layer to optimize a few decisions"