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Commands using echo from sorted by
Terminal - Commands using echo - 1,210 results
while true;do n="$(curl -s http://news.yahoo.com/rss/|sed 's/</\n/g'|grep "title>"|sed -e '/^\// d' -e 's/title>/---------- /g' -e '1,3d'|tr '\n' ' ')";for i in $(eval echo {0..${#n}});do echo -ne "\e[s\e[0;0H${n:$i:$COLUMNS}\e[u";sleep .15;done;done &
2012-11-17 23:56:17
User: SQUIIDUX
Functions: echo eval sleep
7

This creates a permanent stock ticker in the terminal. it has scrolling action and refreshes when each cycle is done to get the latest news.

for file in `ls -t \`find . -name "*.zip" -type f\``; do found=`unzip -c "$file" | grep --color=always "PATTERN"`; if [[ $found ]]; then echo -e "${file}\n${found}\n"; fi done
2012-11-12 15:43:15
User: vladfr
Functions: echo file grep
0

for file in `ls -t \`find . -name "*.zip" -type f\``; do

found=`unzip -c "$file" | grep --color=always "PATTERN"`;

if [[ $found ]]; then echo -e "${file}\n${found}\n"; fi

done

while true; do echo -ne "\e[s\e[0;$((COLUMNS-27))H$(date)\e[u"; sleep 1; done &
2012-11-11 02:16:21
User: SQUIIDUX
Functions: echo sleep
3

This puts a clock in the top right of the terminal. This version doesn't use tput, but uses escape codes

echo "your string here" | tr '\!-~' 'P-~\!-O'
2012-11-06 12:49:00
User: DevEd
Functions: echo tr
1

This command will encode a string using the ROT47 cipher.

java -jar app.jar -cp $(echo lib/*.jar | tr ' ' ':')
2012-10-29 12:51:46
User: xymor
Functions: echo tr
Tags: java cli
0

Lauching an app including jars in an adjacent lib folder to its classpath

for k in `git branch -r|awk '{print $1}'`;do echo -e `git show --pretty=format:"%Cgreen%ci_%C(blue)%c r_%Cred%cn_%Creset" $k|head -n 1`$k;done|sort -r|awk -F"_" '{printf("%s %17s %-22s %s\n",$1,$2,$3,$4)}'
echo -e \\u2620
tail -f /var/log/messages.log | while read line ; do echo $line | cut -d \ -f5- | sed s/\\[[0-9]*\\]// | espeak ; done
echo /home/foo/dir1/bar | awk -F/ -v OFS=/ '{$3 = "dir2"}1'
2012-10-26 16:17:20
User: zlemini
Functions: awk echo
1

Awk replaces the value of a specific field while retaining the field separator "/" .

echo foo | ncat [ip address] [port]
2012-10-26 10:53:47
User: dragonauta
Functions: echo
-1

you can use a pair of commands to test firewalls.

1st launch this command at destination machine

ncat -l [-u] [port] | cat

then use this command at source machine to test remote port

echo foo | ncat [-u] [ip address] [port]

First command will listen at specified port.

It will listen TCP. If you use -u option will listen UDP.

Second command will send "foo" through ncat and will reach defined IP and port.

for i in $(ps -eo pid|grep -v PID);do echo ""; echo -n "==$i== ";awk '/^read|^write/{ORS=" "; print}' /proc/$i/io 2>/dev/null; echo -n " ==$i=="; done|sort -nrk5|awk '{printf "%s\n%s %s\n%s %s\n%s\n\n",$1,$2,$3,$4,$5,$6}'
for i in `ls /var/log/sa/|grep -E "sa[0-9][0-9]"`;do echo -ne "$i -- ";sar -r -f /var/log/sa/$i|awk '{ printf "%3.2f\n",($4-$6-$7)*100/(3+$4)}'|grep -Eiv "average|linux|^ --|0.00|^-" |awk '{sum+=$1 }END{printf "Average = %3.2f%%\n",sum/NR}';done
echo "abcdefg"|awk 'BEGIN {FS="''"} {print $2}'
echo 1268727836 | awk '{print strftime("%c",$1)}'
for i in `ls /sys/class/net/`; do echo $i: `cat /sys/class/net/$i/operstate`; done
2012-10-15 18:20:37
User: dragonauta
Functions: echo
Tags: Network device
0

no need for installing mii-tools, all generic tools

working under archlinux.

for P in $(mount | awk '/type nfs / {print $3;}'); do echo $P; sudo umount $P && sudo mount $P && echo "ok :)"; done
2012-10-14 22:39:58
User: amatix
Functions: awk echo mount sudo umount
Tags: Linux mount nfs
0

`mount -o remount` doesn't pick up new NFS options (eg. timeo, soft, retrans, etc) so you need to do a full mount/remount cycle. This one-liner makes it quick and easy :) Update your fstab with the new options, then run it.

echo 'scale=10; 4*a(1)' | bc -l
2012-10-08 15:03:07
User: chars19
Functions: bc echo
Tags: bc -l
1

a() function in bc is for arctangent, available if using -l option included.

echo "$: << '.'" >> $IRBRC
NUMCPUS=`grep ^proc /proc/cpuinfo | wc -l`; FIRST=`cat /proc/stat | awk '/^cpu / {print $5}'`; sleep 1; SECOND=`cat /proc/stat | awk '/^cpu / {print $5}'`; USED=`echo 2 k 100 $SECOND $FIRST - $NUMCPUS / - p | dc`; echo ${USED}% CPU Usage
2012-10-02 03:57:51
User: toxick
Functions: awk echo sleep wc
0

Using the output of 'ps' to determine CPU usage is misleading, as the CPU column in 'ps' shows CPU usage per process over the entire lifetime of the process. In order to get *current* CPU usage (without scraping a top screen) you need to pull some numbers from /proc/stat. Here, we take two readings, once second apart, determine how much IDLE time was spent across all CPUs, divide by the number of CPUs, and then subtract from 100 to get non-idle time.

while [ 1 ] ; do echo -en "$(date +%T)\r" ; sleep 1; done
for i in $(seq 1 100 | sort -R); do echo $i; sleep 5; done
2012-09-25 17:47:32
Functions: echo seq sleep sort
3

Random choose numbers from 1 to 100 with 5 seconds interval without duplicates.

echo -e "\e[32m"; while :; do printf '%*c' $(($RANDOM % 30)) $(($RANDOM % 2)); done
2012-09-25 17:36:25
Functions: echo printf
Tags: random Matrix
3

Prints 0's and 1's in The Matrix style. You can easily modify to print 0-9 digits using $RANDOM %10 insted of %2.

echo $(</dev/urandom tr -dc 1-6 | head -c1)
echo $((0x$(head -c5 /dev/random|xxd -ps)%6+1))
2012-09-21 02:16:42
User: atoponce
Functions: echo head
9

/dev/random is said to by cryptographically secure, and unpredictable, as it gathers data from external sources, influenced by human timing interactions with computers, to fill the entropy pool. As such, this is a quick way to do a true random fair-6 dice roll. Using this method, you could easily create passphrases with Diceware http://diceware.com.

for i in {1..5}; do echo -n $((0x$(head -c5 /dev/random|xxd -ps)%6+1)); done; echo
( x=`tput op` y=`printf %$((${COLUMNS}-6))s`;for i in {0..256};do o=00$i;echo -e ${o:${#o}-3:3} `tput setaf $i;tput setab $i`${y// /=}$x;done; )