Commands using echo sorted by votes

Commands using echo (1,545)

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Disable ASLR

Disable randomisation address Show Sample Output

-1

echo 0 > /proc/sys/kernel/randomize_va_space

gunslinger_ · 2010-07-11 16:42:42 3

tail all logs opened by all java processes

Tail all logs that are opened by all java processes. This is helpful when you are on a new environment and you do not know where the logs are located. Instead of java you can put any process name. This command does work only for Linux. The list of all log files opened by java process: sudo ls -l $(eval echo "/proc/{$(echo $(pgrep java)|sed 's/ /,/')}/fd/")|grep log|sed 's/[^/]* //g'
This is sample output - yours may be different.
-1

sudo ls -l $(eval echo "/proc/{$(echo $(pgrep java)|sed 's/ /,/')}/fd/")|grep log|sed 's/[^/]* //g'|xargs -r tail -f

vutcovici · 2010-07-30 18:20:00 3
Greets the user appropriately
This is sample output - yours may be different.
-1

echo -e "12 morning\n15 afternoon\n24 evening" | awk '{if ('`date +%H`' < $1) print "Good " $2}'

bazardeur · 2010-09-24 21:15:23 4
Get all the HTTP HEAD responses from a list of urls in a file

urls.txt should have a fully qualified url on each line prefix with rm log.txt; to clear the log change curl command to curl --head $file | head -1 >> log.txt to just get the http status Show Sample Output
This is sample output - yours may be different.
```
==log.txt:==
/downloads HTTP/1.1 301 Moved Permanently
/downloads/ HTTP/1.1 404 Not Found
/downloads/downloads/press/logos.zip HTTP/1.1 200 OK
```
-1

for file in `cat urls.txt`; do echo -n "$file " >> log.txt; curl --head $file >> log.txt ; done

Glutnix · 2010-10-19 02:54:13 5
Get weather

Uses the Wunderground web API to get weather data. Change the STA variable to a station near you. Show Sample Output
This is sample output - yours may be different.
```
West@8.0mph 56.2F
```
-1

STA=KILCHICA30 PAG=http://api.wunderground.com/weatherstation/WXCurrentObXML.asp?ID=${STA} D=($(curl -s $PAG | sed -n 's/.*<$temp_f\|wind_dir\|wind_mph$>$.*$<\/.*/\2/p')) echo ${D[1]}@${D[2]}mph ${D[0]}F

sud0er · 2010-10-28 00:40:28 10
Create a new chrome profile and run it

Change the value of p to match the path where you wish to create the profile. To run it again in the future, use the parameter --user-data-dir (which gets echoed to you when run): chromium-browser --user-data-dir=/path/to/your/ Quick Functions: # create a new chromium profile new-chromium-profile() { p=~/.config/chromium/$1; cp -r ~/.config/chromium/Default $p && echo "chromium-browser --user-data-dir=$p" && chromium-browser --user-data-dir=$p; } # runs a chromium profile run-chromium-profile() { chromium-browser --user-data-dir=~/.config/chromium/$1; } Show Sample Output
This is sample output - yours may be different.
```
chromium-browser --user-data-dir=/home/z/.config/chromium/zed

[A new chrome profile gets created and runs itself.]
```
-1

p=~/.config/chromium/zed; cp -r ~/.config/chromium/Default $p && echo "chromium-browser --user-data-dir=$p" && chromium-browser --user-data-dir=$p;

zed · 2010-11-08 02:45:29 4
get memory configuration (not consumption) for all running VMware virtual machines

So your boss wants to know how much memory has been assigned to each virtual machine running on your server... here's how to nab that information from the command line while logged in to that server Show Sample Output
This is sample output - yours may be different.
```
              aa.devel.mydomain.com.vmx: 1024 M
                 devel.mydomain.com.vmx: 2048 M
                   ftp.mydomain.com.vmx: 256 M
                  mail.mydomain.com.vmx: 256 M
                         testdotnet.vmx: 3072 M
                          testjava2.vmx: 3072 M
                          testjava3.vmx: 3072 M
                           testjava.vmx: 3072 M
                   web.mydomain.com.vmx: 256 M
                              rhel5.vmx: 2048 M
```
-1

for file in $( vmrun list | grep 'vmx$' | sort ); do printf "% 40s %s M\n" $(echo "$( echo -n ${file}:\ ; grep memsize $file )" | sed -e 's/.*\///' -e 's/"//g' -e 's/memsize.=//'); done;

linuxrawkstar · 2010-11-19 06:14:11 3
Function that swaps the filenames of two given files.

(Changed to "bartonskis" suggestion.)
This is sample output - yours may be different.
-1

flipf(){ if [ -f "$1" -a -f "$2" ]; then mv "$1" "$1.$$" && mv "$2" "$1" && mv "$1.$$" "$2" || echo "$!"; else echo "Missing a file: $!"; fi; }

Void42 · 2010-12-16 10:38:28 7
Pick the first program found from a list of alternatives

This function is used to set environmental variables from a list of alternatives depending on what's installed on the system. It returns the first program found in the list. Example usage: export BROWSER=$(find_alternatives chromium-browser google-chrome opera firefox firefox-bin iceweasel konqueror w3m lynx) . export EDITOR=$(find_alternatives vim nano pico emacs kate) . export PAGER=$(find_alternatives vimpager less most more pg)
This is sample output - yours may be different.
-1

find_alternatives(){ for i;do which "$i" >/dev/null && { echo "$i"; return 0;};done;return 1;}

eightmillion · 2011-01-06 19:53:46 3
Terrorist threat level text

Numbers are less understandable then words. Also this may put out a different result.
This is sample output - yours may be different.
-1

echo "Terrorist threat level: `sed $(perl -e "print int rand(99999)")"q;d" /usr/share/dict/words`"

houghi · 2011-01-28 09:49:37 4
Root Security

This will tighten up security for your box. The default value for PermitRootLogin sadly is 'yes'.
This is sample output - yours may be different.
-1

s=/etc/ssh/sshd_config;r=PermitRootLogin;cp $s{,.old}&& if grep $r $s;then sed "s/$r yes/$r no/" $s.old > $s; else echo $r no >> $s;fi

kzh · 2011-01-30 23:41:59 11
Use socat to create a largefile
This is sample output - yours may be different.
-1

echo | socat -u - file:/tmp/swapfile,create,largefile,seek=10000000000000

madrasi · 2011-02-08 00:30:38 4
Tricky implementation of two-dimensional array in Bash
This is sample output - yours may be different.
-1

getarray(){ a=$1;b="${a[$2]}";eval "c=$b";echo "${c[$3]}";return 0;};a[0]="( a b c )";a[1]="( d e f )";getarray a 1 2

glaudiston · 2011-02-20 00:58:41 3
Add a list of numbers
This is sample output - yours may be different.
-1

echo $((1+2+3+4))

dimesacks · 2011-02-24 21:57:44 3
Generate MD5 of string and output only the hash checksum
This is sample output - yours may be different.
-1

echo -n "String to get MD5" | md5sum | sed "s/ -//"

Tephlon · 2011-03-03 23:40:04 3
Generate MD5 of string and output only the hash checksum
This is sample output - yours may be different.
-1

echo -n "String to MD5" | md5sum | awk '{print $1}'

twjolson · 2011-03-05 02:37:28 4
one line command to recursively add all jar files in current folder to java class path

a pretty simple script when running java programs from command line Show Sample Output
This is sample output - yours may be different.
```
.:/home/hyhu/Ubuntu One/javalibs/a.jar:/home/hyhu/Ubuntu One/javalibs/b.jar:/home/hyhu/Ubuntu One/javalibs/c.jar:/home/hyhu/Ubuntu 
```
-1

CLASSPATH=.; export CLASSPATH=$CLASSPATH$(find "$PWD" -name '*.jar' -type f -printf ':%p\n' | sort -u | tr -d '\n'); echo $CLASSPATH

dexterhu · 2011-03-11 19:21:15 3
recursively add all sub folders with executable file of current folder to PATH environment variable

(1) don't run twice, or the same folder will occur in $PATH. (2) otherwise you need to start a new terminal Show Sample Output
This is sample output - yours may be different.
```
blah blah blah ..... (too long)
```
-1

export PATH=$PATH$(find "$PWD" -name '.*' -prune -o -type f -a -perm /u+x -printf ':%h\n' | sort -u | tr -d '\n'); echo $PATH

dexterhu · 2011-03-11 19:31:17 7
Selecting a random file/folder of a folder

Here's a bash version using an array.
This is sample output - yours may be different.
-1

a=(*); echo ${a[$((RANDOM % ${#a[@]}))]}

putnamhill · 2011-03-18 13:24:52 3
Convert filenames from ISO-8859-1 to UTF-8

Warn: use convmv or detox if you can: they are the right tools. But if you want to do it manually, you can use this command to find the problematic files and transliterate their accented characters to their ascii equivalent. (Useful when doing cd backup: growisofs may fail on files which come from the old iso8859-* days.)
This is sample output - yours may be different.
-1

LANG=fr_FR.iso8859-1 find . -name '*['$'\xe9'$'\xea'$'\xeb'$'\xc9'']*'|while read f; do a="$(echo $f|iconv -f iso8859-1 -t ascii//TRANSLIT)"; echo "move $f => $a"; done

gibboris · 2011-04-06 17:03:31 3
Check a internet connetion is up. If it isn't write a log.

This command are using by me for checking connection with Internet. Show Sample Output
This is sample output - yours may be different.
```
8.8.8.8 ping failed at 12/05/11 12:48:28
8.8.8.8 ping failed at 12/05/11 12:48:41
```
-1

while true; do /bin/ping -q -c1 -w3 8.8.8.8 2>&1 > /dev/null || echo "8.8.8.8 ping failed at $(date +%d/%m/%y) $(date +%H:%M:%S)" >> /var/log/ping.log; sleep 10; done &

Arkey · 2011-05-12 01:51:07 4
Show seconds since modified of newest modified file in directory
This is sample output - yours may be different.
-1

echo $(( $( date +%s ) - $( stat -c %Y * | sort -nr | head -n 1 ) ))

depesz · 2011-05-12 14:29:45 3
urldecoding

urldecode files in current directrory
This is sample output - yours may be different.
-1

ls * | while read fin;do fout=$(echo -n $fin | sed -e's/%$[0-9A-F][0-9A-F]$/\\\\\x\1/g' | xargs echo -e);if [ "$fout" != "$fin" ];then echo "mv '$fin' '$fout'";fi;done | bash -x

pawelb1973 · 2011-05-18 07:24:54 82
Send an email using the mutt email client

It's very similar to this thread: http://www.commandlinefu.com/commands/view/4317/send-a-local-file-via-email mutt your@email_address.com -s "Message Subject Here" -a attachment.jpg </dev/null
This is sample output - yours may be different.
-1

M=bob@example.com; echo "Email message" | mutt -s "Email Subject" $M

igorfu · 2011-05-23 08:31:14 11
monitor when target host will be up
This is sample output - yours may be different.
-1

while true; do date; ssh <YOUR HOST HERE> "echo" && echo "HOST UP" && break; sleep 60; done

unixmonkey11685 · 2011-05-29 19:54:16 3
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Grab IP address on machine with multiple interfaces

Instead of hard-coding in a check to scrape info from ifconfig based on a specific interface, do it in a more portable way. This works really well if you switch between wired, wireless, bluetooth or even VPN connections. You can get your current IP in a script (since it'll be something like tun0 instead of eth0 or wlan1). This uses a well known public ip address 8.8.8.8, but it doesn't actually connect to it, it just shows you the route it would take.

Mount a partition from within a complete disk dump

Suppose you made a backup of your hard disk with dd: dd if=/dev/sda of=/mnt/disk/backup.img This command enables you to mount a partition from inside this image, so you can access your files directly. Substitute PARTITION=1 with the number of the partition you want to mount (returned from sfdisk -d yourfile.img).

How To Get the Apache Document Root

Grabs the Apache config file (yielded from httpd) and returns the path specified as DocumentRoot.

Lists all clients of a Squid proxy

Generates the list of clients (IPs addresses) that have used the Squid webproxy according to the most recent log. Every IP appears only once in the list.

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

check open ports without netstat or lsof

Find Mac address

Compare copies of a file with md5

I had the problem that the Md5 Sum of a file changed after copying it to my external disk. This unhandy command helped me to fix the problem.

Get AWS temporary credentials ready to export based on a MFA virtual appliance

You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Get max number of arguments

Get max number of arguments that can be accepted by the exec() system call.

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Commands using echo (1,545)

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