Commands using echo sorted by votes

Commands using echo (1,545)

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Check SSL crt and key compatibility
This is sample output - yours may be different.
0

KEY_HASH=`openssl rsa -in $KEY_PATH -modulus -noout | openssl md5` && CRT_HASH=`openssl x509 -in $CERT_PATH -modulus -noout | openssl md5`; if [ "$KEY_HASH" != "$CRT_HASH" ];then echo "MD5 sums between .key and .crt files DO NOT MATCH";fi

kernel01 · 2013-08-13 11:09:23 7
all java -Xmx values in a system, add them up

This will find all the -Xmx[BIGINT] running on a system, add them up for you and give you the total. Show Sample Output
This is sample output - yours may be different.
```
39424
```
0

output=$(ps -ef|grep -i java 2>/dev/null); for w in ${output[@]}; do if [[ $w =~ .*Xmx.* ]]; then result=$(grep -oP "[0-9]+" <<< $w); echo $result ;fi ; done| awk 'BEGIN {sum=0} {for(i=1; i<=NF; i++) sum+=$i } END {print sum}'

massiverobot · 2013-08-13 14:04:17 7
Detect broken video files with mplayer and bash in the current directory

If you want avoid to be annoyed when playing your favourite video files with your video player, first run this command to stash wrong files (and test tricks to play these wrong files). Show Sample Output
This is sample output - yours may be different.
```
# annoying and the video file won't play :
$ mplayer file.mkv
...
[h264 @ 0x6ad23b85af8e6]no frame!
Error while decoding frame!
...
# so test my command before
```
0

for i in *.flv *.mkv *.avi; do mplayer -ao null -vo null -ss 0 -endpos 1 >/dev/null "$i" 2> >(grep -qi error && echo >&2 "$i seems bad"); done

sputnick · 2013-08-20 22:23:11 11
Generate an XKCD #936 style 4 word password
This is sample output - yours may be different.
0

word=$(shuf -n4 /usr/share/dict/words); for w in ${word[@]}; do w=${w^}; w=${w//\'/}; p+=$w; done; echo $p

fishdaemon · 2013-08-22 08:21:41 8
find an unused unprivileged TCP port

Should work with sh, bash, etc. Show Sample Output
This is sample output - yours may be different.
```
32768
```
0

port=32768; while netstat -atn | grep -q :$port; do port=$(expr $port + 1); done; echo $port

presto8 · 2013-08-29 17:55:55 8
Find a machine's IP address and FQDN
This is sample output - yours may be different.
0

for i in `ip addr show dev eth1 | grep inet | awk '{print $2}' | cut -d/ -f1`; do echo -n $i; echo -en '\t'; host $i | awk '{print $5}'; done

BoxingOctopus · 2013-09-05 17:50:33 7
IBM AIX: Calculate the SHA256 hashes of a directory without sha256sum

This command is for producing GNU sha256sum-compatible hashes on UNIX systems that don't have sha256sum but do have OpenSSL, such as stock IBM AIX. 1.- Saves a wrapper script for UNIX find that does the following: A.- Feeds a file to openssl on SHA256 hash calculation mode B.- Echoes the output followed by the filename 2.- Makes the file executable 3.- Runs find on a directory, only processing files, and running on each one the wrapper script that calculates SHA256 hashes Pending is figuring out how to verify a sha256sum file on a similar environment. Show Sample Output
This is sample output - yours may be different.
```
6e94b0b7fc2805ad558f8039ed038a6272f61846eaa5f4931abd826193c78b83 cognos-installers/TM1-952-AIX/952_FP2_aix.tar.gz
c9d0f04ad6f86482bf4c41ba7a303e0d8a0e8c96c9c9492bc518d2a2bc0166c7 cognos-installers/TM1-952-AIX/952_FP2_HF6_aix.tar.gz
46ede3255abff4e356b002a9cd12df259275a15910768997bfbbae3c637b7f32 cognos-installers/TM1-952-windows/TM1_9.5.2_Windows_x64.7z
92faf20dd3ff25d2c8d94308f03fd8477d0980d6b740baa96a8e79b30b49456f cognos-installers/TM1-952-windows/TM1_Workflow_9.5.2_Windows_x64.7z
630a66a1f7cc3044f370cec730820d73d66cb284a2a09e197c00f82d6900d932 cognos-installers/cognos-BI-102/cognos-FM/fm_10.2_win_ml.tar.xz
```
0

echo '#! /usr/bin/ksh\necho `cat $1 | openssl dgst -sha256` $1' > sslsha256; chmod +x sslsha256; find directory -type f -exec ./sslsha256 \{\} \;

RAKK · 2013-09-18 17:37:50 8
IBM AIX: Verify a sha256sum listing with openssl

This command is used to verify a sha256sum-formatted file hash list on IBM AIX or any other UNIX-like OS that has openssl but doesn't have sha256sum by default. Steps: 1: Save to the filesystem a script that: A: Receives as arguments the two parts of one line of a sha256sum listing B: Feeds a file into openssl on SHA256 standard input hash calculation mode, and saves the result C: Compares the calculated hash against the one received as argument D: Outputs the result in a sha256sum-like format 2: Make the script runnable 3: Feed the sha256sum listing to xargs, running the aforementioned script and passing 2 arguments at a time Show Sample Output
This is sample output - yours may be different.
```
cognos-EARs/ServletGateway-1021-SDK-customized.ear: OK
cognos-EARs/ServletGateway-1021-SDK-customizedandfixed.ear: OK
cognos-EARs/ServletGateway-1021-base.ear: OK
cognos-EARs/p2pd-1021-SDK-customized.ear: OK
cognos-EARs/p2pd-1021-base.ear: OK
```
0

echo '#! /usr/bin/ksh\ncat $2 | openssl dgst -sha256 | read hashish; if [[ $hashish = $1 ]]; then echo $2: OK; else echo $2: FAILED; fi;' > shacheck; chmod +x shacheck; cat hashishes.sha256 | xargs -n 2 ./shacheck;

RAKK · 2013-09-18 21:51:20 8
Display terminal command history with date

If the HISTTIMEFORMAT is set, the time stamp information associated with each history entry is written to the history file, marked with the history comment character. Show Sample Output
This is sample output - yours may be different.
```
    2  19/09/13 11:21:02 ./adb kill-server
    3  19/09/13 11:21:02 ./adb start-server
    4  19/09/13 11:21:02 ./adb 
    5  19/09/13 11:21:02 ./adb shell
    6  19/09/13 11:21:02 ./adb shell
    7  19/09/13 11:21:02 cd /Users/weng/Software/android-sdk-macosx/platform-tools/
    8  19/09/13 11:21:02 ./adb kill-server
    9  19/09/13 11:21:02 ./adb start-server
   10  19/09/13 11:21:02 ping 192.168.1.10
```
0

echo 'export HISTTIMEFORMAT="%d/%m/%y %T "' >> ~/.bash_profile

99RedBalloons · 2013-09-19 03:25:14 13
countdown from 10 ...
This is sample output - yours may be different.
0

clear; tput cup 8 8; for i in $(seq 1 10); do echo -n "$((11-$i)) ";sleep 1; done; tput cup 10 8; echo -e "DONE\n\n"

rgregor · 2013-10-01 11:21:25 6
Print out the contents of a Git repository (useful for broken repositories)
This is sample output - yours may be different.
0

find .git/objects -type f -printf "%P\n" | sed s,/,, | while read object; do echo "=== $obj $(git cat-file -t $object) ==="; git cat-file -p $object; done

hamador · 2013-10-02 09:09:00 10
strips ogg audio from webm video ( no reencoding )

Strips the audio track from a webm video. Use this in combination with clive or youtube-dl.
This is sample output - yours may be different.
0

for file in "$@"; do name=$(basename "$file" .webm) echo ffmpeg -i $file -vn -c:a copy $name.ogg ffmpeg -i "$file" -vn -c:a copy "$name.ogg" done

hoodie · 2013-10-05 14:49:07 9
Generate a Random (unicast) MAC address

I did not come up with this one myself, but found this somewhere else several months ago. Show Sample Output
This is sample output - yours may be different.
```
E0:C9:B3:FE:E9:65
```
0

openssl rand -hex 1 | tr '[:lower:]' '[:upper:]' | xargs echo "obase=2;ibase=16;" | bc | cut -c1-6 | sed 's/$/00/' | xargs echo "obase=16;ibase=2;" | bc | sed "s/$/:$(openssl rand -hex 5 | sed 's/$..$/\1:/g; s/.$//' | tr '[:lower:]' '[:upper:]')/"

4fd · 2013-10-22 08:40:46 7
creating you're logging function for your script

Put this logging function in you're script, when need it call it. command || logme "Error with command"
This is sample output - yours may be different.
0

logme(){ echo "$(date +%d-%m-%Y-%H:%M) => $0 @ $1 returned error" >> persoscript.log }

qcjn · 2013-10-22 15:55:01 6
Command line email/SMS Bomber

To send a text message to a phone, you need to send the text message via email. To find out how to send text messages to cell phones via email, go here - http://en.wikipedia.org/wiki/List_of_carriers_providing_Email_or_Web_to_SMS and find the carrier of the cell phone you want to send the text message to.
This is sample output - yours may be different.
0

while true; do echo "message here" | mutt something@something.com ; done

KcidKcus · 2013-10-27 23:32:54 79
Delete keys from Redis by matching a pattern

Delete items from Redis, using redis-cli, by matching a key pattern. Show Sample Output
This is sample output - yours may be different.
```
(integer) 1
(integer) 1
(integer) 1
(integer) 1
(integer) 1
```
0

for key in `echo 'KEYS pattern*' | redis-cli | awk '{print $1}'`; do echo DEL $key; done | redis-cli

caiosba · 2013-10-29 04:50:35 10
Use awk's FIELDWIDTHS function to manipulate a string.
This is sample output - yours may be different.
0

echo "rootgot" | awk 'BEGIN{FIELDWIDTHS="4 3"}{print $2$1}'

in2nix4life · 2013-11-06 14:17:37 6
Generate a random password.

Uses urandom and tr to generate a random password. Change the value of head -c## for the lenght of the password. Show Sample Output
This is sample output - yours may be different.
```
dWl2GEd7RE
```
0

echo $(< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c10)

santizo · 2013-11-07 21:51:38 7
Check if TCP port 25 is open

Check trough unix sockets if tcp port is open or close Show Sample Output
This is sample output - yours may be different.
```
TCP port 25 close
```
0

(echo >/dev/tcp/localhost/25) &>/dev/null && echo "TCP port 25 open" || echo "TCP port 25 close"

YouM · 2013-11-12 02:11:01 8
One line web server (working with any web browser)

nc is such a powerful command, it could be used instead of any OS! :p Show Sample Output
This is sample output - yours may be different.
```
/home/me> curl -i localhost:5432
HTTP/1.1 200 OK
Tue Nov 12 15:40:27 EET 2013


<p>How are you today?</p>
```
0

nc -kl 5432 -c 'echo -e "HTTP/1.1 200 OK\r\n$(date)\r\n\r\n";echo "<p>How are you today?</p>"'

gvitalie · 2013-11-12 13:43:38 6
Mass rename files in git

Taken from http://stackoverflow.com/questions/9984722/git-rename-many-files-and-folders
This is sample output - yours may be different.
0

for file in $(git ls-files | grep old_name_pattern); do git mv $file $(echo $file | sed -e 's/old_name_pattern/new_name_pattern/'); done

lpalgarvio · 2013-11-19 18:33:23 7
To display the message

This will display --> Hello World
This is sample output - yours may be different.
0

echo "Hello WOrld"

Abhay_k · 2013-11-24 10:26:50 6
Run a command in every (direct) sub-folder

Change the "run_command" to whatever command you want, and remove the "echo" to run it once you are happy.
This is sample output - yours may be different.
0

for i in */; do echo run_command "${i}"; done

mirams · 2013-11-25 18:33:26 9
one liner to rename files with for and sed

If you want to test output, run it like this: for fn in *.epub; do echo mv \"$fn\" \"`echo "$fn" | sed -E 's/\.*\/*(.*)( - )(.*)(\.[^\.]+)$/\3\2\1\4/' | sed -E 's/(.*) ([^ ]+)( - )(.*)/\2, \1\3\4/' `\";done > rename.txt Show Sample Output
This is sample output - yours may be different.
```
Input filename: The Big Wave - Pearl S. Buck.epub
Output: Buck, Pearl S. - The Big Wave.epub
```
0

for fn in *.epub; do echo mv \"$fn\" \"`echo "$fn" | sed -E 's/\.*\/*(.*)( - )(.*)(\.[^\.]+)$/\3\2\1\4/' | sed -E 's/(.*) ([^ ]+)( - )(.*)/\2, \1\3\4/' `\";done | sh

woohoo · 2013-11-30 05:29:52 6
Count music files in each directory

This lists the number of ogg/mp3/wav/flac files in each subdirectory of the current directory. The output can be sorted by piping it into "sort -n". Show Sample Output
This is sample output - yours may be different.
```
9955 .
82 ./16 Horsepower
17 ./17 Hippies
11 ./Abney Park
44 ./AC DC
10 ./Accept
1 ./Acceptance
9 ./Adiemus
6 ./Bran? Ketern?
10 ./Budapest Gypsy Symphony Orchestra
20 ./Budapester Klezmer Band
35 ./Buena Vista Social Club
12 ./Burlap To Cashmere
```
0

find . -type d -maxdepth 1 -print0 | xargs -0 -I{} sh -c 'find "{}" -type f | grep "ogg\|mp3\|wav\|flac$" | wc -l | tr -d "\n"; echo " {}"'

dbrgn · 2013-12-22 13:40:29 11
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Advanced python tracing

Trace python statement execution and syscalls invoked during that simultaneously

list block devices

Shows all block devices in a tree with descruptions of what they are.

Efficient count files in directory (no recursion)

$ time perl -e 'if(opendir D,"."){@a=readdir D;print $#a - 1,"\n"}' 205413 real 0m0.497s user 0m0.220s sys 0m0.268s $ time { ls |wc -l; } 205413 real 0m3.776s user 0m3.340s sys 0m0.424s ********* ** EDIT: turns out this perl liner is mostly masturbation. this is slightly faster: $ find . -maxdepth 1 | wc -l sh-3.2$ time { find . -maxdepth 1|wc -l; } 205414 real 0m0.456s user 0m0.116s sys 0m0.328s ** EDIT: now a slightly faster perl version $ perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' sh-3.2$ time perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' 205414 real 0m0.415s user 0m0.176s sys 0m0.232s

Detect illegal access to kernel space, potentially useful for Meltdown detection

Based on capsule8 agent examples, not rigorously tested

list files recursively by size

SVN script for automatically adding and deleting files

dd with progress bar and statistics to gzipped image

Delete files older than..

This command will delete files i a given path (/dir_name) , which older than given time in days (-mtime +5 will delete files older than five days.

defragment files

Thanks to flatcap for optimizing this command. This command takes advantage of the ext4 filesystem's resistance to fragmentation. By using this command, files that were previously fragmented will be copied / deleted / pasted essentially giving the filesystem another chance at saving the file contiguously. ( unlike FAT / NTFS, the *nix filesystem always try to save a file without fragmenting it ) My command only effects the home directory and only those files with your R/W (read / write ) permissions. There are two issues with this command: 1. it really won't help, it works, but linux doesn't suffer much (if any ) fragmentation and even fragmented files have fast I/O 2. it doesn't discriminate between fragmented and non-fragmented files, so a large ~/ directory with no fragments will take almost as long as an equally sized fragmented ~/ directory The benefits i managed to work into the command: 1. it only defragments files under 16mb, because a large file with fragments isn't as noticeable as a small file that's fragmented, and copy/ delete/ paste of large files would take too long 2. it gives a nice countdown in the terminal so you know how far how much progress is being made and just like other defragmenters you can stop at any time ( use ctrl+c ) 3. fast! i can defrag my ~/ directory in 11 seconds thanks to the ramdrive powering the command's temporary storage bottom line: 1. its only an experiment, safe ( i've used it several times for testing ), but probably not very effective ( unless you somehow have a fragmentation problem on linux ). might be a placebo for recent windows converts looking for a defrag utility on linux and won't accept no for an answer 2. it's my first commandlinefu command

Combine multiple images into a video using ffmpeg

The -start_number can be ignored if sequence starts with 0, otherwise use first number in sequence

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Commands using echo (1,545)

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