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FizzBuzz in one line of Bash

The (in)famous "FizzBuzz" programming challenge, answered in a single line of Bash code. The "|column" part at the end merely formats the output a bit, so if "column" is not installed on your machine you can simply omit that part. Without "|column", the solution only uses 75 characters. The version below is expanded to multiple lines, with comments added. for i in {1..100} # Use i to loop from "1" to "100", inclusive. do ((i % 3)) && # If i is not divisible by 3... x= || # ...blank out x (yes, "x= " does that). Otherwise,... x=Fizz # ...set x to the string "Fizz". ((i % 5)) || # If i is not divisible by 5, skip (there's no "&&")... x+=Buzz # ...Otherwise, append (not set) the string "Buzz" to x. echo ${x:-$i} # Print x unless it is blanked out. Otherwise, print i. done | column # Wrap output into columns (not part of the test). Show Sample Output
This is sample output - yours may be different.
```
1        16       31       46       61       76       91
2        17       32       47       62       77       92
Fizz     Fizz     Fizz     Fizz     Fizz     Fizz     Fizz
4        19       34       49       64       79       94
Buzz     Buzz     Buzz     Buzz     Buzz     Buzz     Buzz
Fizz     Fizz     Fizz     Fizz     Fizz     Fizz     Fizz
7        22       37       52       67       82       97
8        23       38       53       68       83       98
Fizz     Fizz     Fizz     Fizz     Fizz     Fizz     Fizz
Buzz     Buzz     Buzz     Buzz     Buzz     Buzz     Buzz
11       26       41       56       71       86
Fizz     Fizz     Fizz     Fizz     Fizz     Fizz
13       28       43       58       73       88
14       29       44       59       74       89
FizzBuzz FizzBuzz FizzBuzz FizzBuzz FizzBuzz FizzBuzz
```
1

for i in {1..100};do((i%3))&&x=||x=Fizz;((i%5))||x+=Buzz;echo ${x:-$i};done|column

willdye · 2017-08-22 15:44:16 19
pipe remote log web server file to lostalgia

logstalgia must be installed
This is sample output - yours may be different.
0

ssh -n user@server.tr tail -f /usr/local/nginx/logs/access.log > /tmp/access | tail -f /tmp/access | logstalgia

aysadk · 2017-08-19 16:55:09 17
burn iso to usb

usb must be bootable with rufus or other
This is sample output - yours may be different.
0

dd if=/daten/isos/debian-8.8.0-i386-netinst.iso of=/dev/sdb bs=4M

aysadk · 2017-08-18 22:48:32 28
nmap all my hosts in EC2

List all your public IPs in an EC2/AWS region, and run an nmap scan against them (ignoring ping response). Requires: aws cli, jq for shell JSON processing Show Sample Output
This is sample output - yours may be different.
```
Starting Nmap 7.40 ( https://nmap.org ) at 2017-08-18 13:51 EDT
Stats: 0:00:13 elapsed; 0 hosts completed (22 up), 22 undergoing Connect Scan
Connect Scan Timing: About 0.23% done

[...]
```
0

nmap -P0 -sV `aws --output json ec2 describe-addresses | jq -r '.Addresses[].PublicIp'` | tee /dev/shm/nmap-output.txt

NightMonkey · 2017-08-18 17:55:13 17
du show hidden files all files
This is sample output - yours may be different.
0

du -sch .[!.]* * |sort -h

aysadk · 2017-08-17 20:46:15 21
nmap -sP 192.168.1.*
This is sample output - yours may be different.
0

nmap find alive hosts

aysadk · 2017-08-17 11:04:08 14
nmap check port
This is sample output - yours may be different.
0

sudo nmap -sU -p 53 8.8.8.8

aysadk · 2017-08-16 19:59:18 17
nc check udp port
This is sample output - yours may be different.
0

nc -vz -u 8.8.8.8 53

aysadk · 2017-08-16 19:57:42 17
Change all the files on your system that have the OLDGID group by the new NEWGID.

It's change the group id of all the files on your system that have the OLDGID group as the owner group by the new NEWGID. But first do this: Document which files will be changed, use: find / -gid OLDGID ! -type l > resplado-gid.txt Be sure to disconnect users from the old group. Stop demons or services associated with the group. Be sure the new group exist and take note of GID
This is sample output - yours may be different.
0

$ find / -gid OLDGID ! -type l -exec chgrp NEWGID {} \;

rcorrea · 2017-08-09 21:37:51 18
list size and directies in curretn folder
This is sample output - yours may be different.
0

du -sh ./*/

aysadk · 2017-08-08 15:05:21 20
in current directory delete all files with ending
This is sample output - yours may be different.
0

find . -name "*.bak" -type f -delete

aysadk · 2017-08-08 15:04:33 17
Download an entire website
This is sample output - yours may be different.
0

wget -mkEpnp example.com

prabhakaran9397 · 2017-08-05 19:45:03 155
find the path of biggest used space
This is sample output - yours may be different.
0

du -a / | sort -n -r | head -n 10

aysadk · 2017-08-04 12:34:38 17
Sync copy directories except (OSX)
This is sample output - yours may be different.
0

rsync -rP --exclude=x source/ target/

ctcrnitv · 2017-08-03 22:08:01 17
Find logs modified in the last 15 minutes

This is a regular find with the -wholename parameter to let it know what name pattern he need to look and then the -mmin -15 to know the last 15 minutes. Show Sample Output
This is sample output - yours may be different.
```
/var/log/sssd/sssd_nss.log
/var/log/audit/audit.log
```
0

find /var/log -wholename "*.log" -mmin -15

x3mboy · 2017-08-03 15:47:43 15
split & combine a large file

To recombine split files: cat file.gz.part* > file.gz Show Sample Output
This is sample output - yours may be different.
```
file.gz.part-aa, files file.gz.part-ab
```
0

split -b 500m file.gz file.gz.part-

mayurpant · 2017-08-02 12:05:40 18
get with grep exact x strings matches from output
This is sample output - yours may be different.
0

grep "^[A-Za-z0-9]\{6\}$" myfile.txt

aysadk · 2017-08-01 14:54:25 17
Show lines that are not commented out
This is sample output - yours may be different.
0

grep "^[^#;]" /etc/php.ini

tlezotte · 2017-07-31 18:48:01 17
Delete huge numbers of files without intensive cpu load

I needed to find a command to delete huge numbers of files without intensive cpu load, that command does the job :) The purpose of "+" at then end of the line, tells rm to delete multiple files at once
This is sample output - yours may be different.
0

find <path> -type f -exec ionice -c3 rm {} +

tyjak · 2017-07-31 09:35:36 25
Disable password expiration and clear password history for VMware vcenter appliance

Disable password expiration and clear password history for VMware vcenter appliance
This is sample output - yours may be different.
0

chage -M -1 root; echo "" > /etc/security/opasswd

tsener · 2017-07-30 21:26:43 52
send attachment file email
This is sample output - yours may be different.
0

echo "This is the message body" | mutt -a "/path/to/file.to.attach" -s "subject of message" -- recipient@domain.com

aysadk · 2017-07-28 13:58:10 17
Linux socket-to-socket tunnel (MySQL example)

Won't work with password login. You must add your RSA key to the server's authorizedkeys file, or change the ssh command adding the -i option for a custom RSA key: socat "UNIX-LISTEN:/tmp/mysqld.temp.sock,reuseaddr,fork" EXEC:"ssh username@remoteserver.com -i /home/user/rsa-keys/id_rsa socat STDIO UNIX-CONNECT\:/var/run/mysqld/mysqld.sock" --- /tmp/mysqld.temp.sock will be created locally by socat, don't create it yourself. The folder it lives must be writable. Connect your MySQL client to this socket, with database and username set properly. --- In case you need to forward a remote socket to a LOCAL PORT instead, check http://www.commandlinefu.com/commands/view/9436/socat-tcp-listen5500-execssh-userremotehost-socat-stdio-unix-connectvarrunmysqldmysqld.sock
This is sample output - yours may be different.
0

socat "UNIX-LISTEN:/tmp/mysqld.temp.sock,reuseaddr,fork" EXEC:"ssh username@remoteserver.com socat STDIO UNIX-CONNECT\:/var/run/mysqld/mysqld.sock"

paulera · 2017-07-27 11:32:19 49
send message to specific remote user

pts/33 is variable you can do before you send message to on which pts the user is following ssh youraccount@192.168.1.168 who
This is sample output - yours may be different.
0

ssh youraccount@192.168.1.168 write toUsername pts/33

aysadk · 2017-07-27 10:25:38 21
Unzip all zip files in a directory into a newly created directory based on zip file name

For some reason some people do not place files into folders before archiving. This fixes the mess by creating new directories per zip file in directory to unzip to. Show Sample Output
This is sample output - yours may be different.
```
Archive: ABC.zip
extracting: ABC/1
extracting: ABC/2
Archive: DEF.zip
extracting: DEF/1
extracting: DEF/2
```
0

for f in *.zip; do unzip -d "${f%*.zip}" "$f"; done

osu · 2017-07-26 22:26:22 16
Copy a file over SSH without SCP
This is sample output - yours may be different.
0

cat file | ssh user@remotehost "cat > file"

luckyone777 · 2017-07-26 20:36:02 18
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Find files of two different extensions and copy them to a directory

Use nroff to view the man pages

Using nroff , it is possible to view the otherwise garbled man page with col command.

Install pip with Proxy

Installs pip packages defining a proxy

Write comments to your history.

A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

encode HTML entities

Encodes HTML entities from input (file or stdin) so it's possible to directly past the result to a blog or HTML source file.

ls not pattern

I've been looking for a way to do this for a while, get a not pattern for shell globs. This works, I'm using to grab logs from a remote server via scp.

Connect via sftp to a specific port

I use this for connect via sftp to a server listening on a non default ssh port.

useful tail on /var/log to avoid old logs or/and gzipped files

with discard wilcards in bash you can "tail" newer logs files to see what happen, any error, info, warn...

print date 24 hours ago

List all files ever added in git repository

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