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Download SSL/TLS pem format cert from https web host
This is sample output - yours may be different.
0

openssl s_client -showcerts -connect google.com:443 </dev/null 2>/dev/null|openssl x509 -outform PEM > /tmp/google.com.cer

zhangtai · 2021-09-24 02:37:00 0
Add a DNS server on the fly

Since systemd-resolved was implemented, add a DNS server have become weirder and harder than before. With this command, you can add a DNS server on-the-fly tied to an specific interface
This is sample output - yours may be different.
1

sudo systemd-resolve --interface <NombreInterfaz> --set-dns <IPDNS> --set-domain mydomain.com

x3mboy · 2021-09-21 14:43:48 12
Windows telnet

Check if TCP port is reacheable Show Sample Output
This is sample output - yours may be different.
```
ComputerName     : ecample.com
RemoteAddress    : 192.168.1.59
RemotePort       : 443
InterfaceAlias   : SRV-37
SourceAddress    : 192.168.1.10
TcpTestSucceeded : True
```
0

Test-NetConnection -ComputerName example.com -Port 443

EBAH · 2021-09-16 16:11:04 10
Superfast portscanner
This is sample output - yours may be different.
0

time seq 65535 | parallel -k --joblog portscan -j9 --pipe --cat -j200% -n9000 --tagstring '\033[30;3{=$_=++$::color%8=}m' 'nc -vz localhost $(head -n1 {})-$(tail -n1 {})'

wuziduzi · 2021-09-14 16:15:51 21
Clear Cached Memory on Ubuntu

Clear Cached Memory on Ubuntu based distributions, and also display memory status. Please do not use this on a production machine unless you really really know what you are doing. Echo 3 is a kinder way of purging the memory, you can also use 'echo 2' or 'echo 1' if #1 You know what you are doing, and #2 refer to number 1 :-)
This is sample output - yours may be different.
0

sudo free && sync && sudo echo 3 | sudo tee /proc/sys/vm/drop_caches

tg0000 · 2021-09-13 16:45:20 6
Check a directory of PNG files for errors

Useful for checking if a large number of PNG files was downloaded successfully by verifying the built-in CRC checksum. For incomplete files, the command will print: "00002309.png EOF while reading IDAT data ERROR: 00002309.png" The process is very fast; checking 21,000 files of 5MB in size took only five minutes on a 2011 Intel mobile dual-core.
This is sample output - yours may be different.
0

ls *.png |parallel --nice 19 --bar --will-cite "pngcheck -q {}"

Negate · 2021-09-05 00:37:07 26
Banner Grabber
This is sample output - yours may be different.
0

bash -c 'exec 3<>/dev/tcp/google.com/80; echo EOF>&3; cat<&3'

wuziduzi · 2021-09-03 00:18:05 15
generate pem cert from host with ssl port
This is sample output - yours may be different.
0

openssl s_client -connect HOSTNAME.at:443 -showcerts </dev/null 2>/dev/null | openssl x509 -outform PEM > meinzertifikat.pem

dbiesecke · 2021-09-01 14:05:36 14
Get all lines that start with a dot or period

Read a file or standard input and only outputs lines that start with a dot or period "." Show Sample Output
This is sample output - yours may be different.
```
.config
```
0

grep '^\.' file

bugmenot · 2021-08-22 16:04:11 35
Store Host IP in variable
This is sample output - yours may be different.
-1

export IP="$(hostname -I | awk '{print $1}')"

wuziduzi · 2021-08-10 03:48:21 23
Download mp3 files linked in a RSS podcast feed

Directly download all mp3 files of the desired podcast
This is sample output - yours may be different.
0

curl http://radiofrance-podcast.net/podcast09/rss_14726.xml | grep -Eo "(http|https)://[a-zA-Z0-9./?=_%:-]*mp3" | sort -u | xargs wget

pascalv · 2021-08-09 13:40:26 40
Color STDERR in output

This command will take the output of a command and color any STDERR output as a different color (red outline in this case) Show Sample Output
This is sample output - yours may be different.
```
This is a normal line
This is an error line # this is red outlined
```
2

./errorscript.sh 2> >(echo "\e[0;41m$(cat)\e[0m")

tyzbit · 2021-08-08 14:28:50 34
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
This is sample output - yours may be different.
0

ffmpeg -start_number 0053 -r 1/5 -i IMG_%04d.JPG -c:v libx264 -vf fps=25 -pix_fmt yuv420p out.mp4

alikhalil · 2021-08-01 12:39:44 34
premiumize - create a ddl & save the URL in variable MYLINK
This is sample output - yours may be different.
1

MYLINK=$(curl 'https://www.premiumize.me/api/transfer/directdl?apikey=dzx3rqwrxme8iazu' \ -H 'accept: application/json' \ -H 'Content-Type: application/x-www-form-urlencoded' --data-raw 'src='$URL | jq -r '.content[] | .link' )

dbiesecke · 2021-07-25 09:20:31 25

Offcloud - add a link as remote download

You will get an json respond if all is fine Show Sample Output

curl 'https://offcloud.com/api/remote?key=XXXXXX' \ -H 'accept: application/json' \ -H 'Content-Type: application/x-www-form-urlencoded' --data-raw "url=$MYLINK&remoteOptionId=XXXXX"

dbiesecke · 2021-07-25 09:19:14 34

checks size of directory & delete it if its to small

only simple example how to combine rclone & jq Show Sample Output
This is sample output - yours may be different.
```
Transferred:              0 / 0 Byte, -, 0 Byte/s, ETA -
Errors:                 1 (retrying may help)   
Deleted:                0 (files), 3 (dirs)
Elapsed time:        14.2sTransferred:                    0 / 0 Byte, -, 0 Byte/s, ETA -
Errors:                 1 (retrying may help)
Deleted:                0 (files), 3 (dirs)
Elapsed time:        14.2s
2021/07/25 11:14:04 Failed to purge: unlinkat /mnt/anime/Anime/Fansub/Basquash! (2009): input/output error
```
1

for i in *; do test -d "$i" && ( rclone size "$i" --json -L 2> /dev/null | jq --arg path "$i" 'if .bytes < 57462360 then ( { p: $path , b: .bytes}) else "none" end' | grep -v none | jq -r '.p' | parallel -j3 rclone purge "{}" -v -P ); done

dbiesecke · 2021-07-25 09:16:03 20
Get a range on line with sed (first two)

Get the two first lines of a file and quit. Show Sample Output
This is sample output - yours may be different.
```
first-line
second-line
```
1

sed -n '1,2p;3q' file

bugmenot · 2021-07-16 07:29:15 25
Remove all the characters before last space per line including it
This is sample output - yours may be different.
1

echo 'The quick brown fox jumps over the lazy dog' | sed 's|.* ||'

bugmenot · 2021-07-16 07:17:08 19
Get line number 12 (or n) from a file

Extracts only file number 12 from file. It's meant for text files. Replace 12 with the number you want. First line starts at 1 not 0. We use q on next line so doesn't process any line more.
This is sample output - yours may be different.
1

sed -n '12p;13q' file

bugmenot · 2021-07-15 20:13:05 16
Replace all forward slashes with backward slashes

Use -i option to edit directly a file: sed -i 's|\/|\\|g' file Show Sample Output
This is sample output - yours may be different.
```
\usr\bin\
```
2

echo '/usr/bin/' | sed 's|\/|\\|g'

bugmenot · 2021-07-15 20:09:34 30
Replace all backward slashes with forward slashes

Use -i to edit file directly: sed -i 's|\\|\/|g' file Show Sample Output
This is sample output - yours may be different.
```
C:/Windows/
```
1

echo 'C:\Windows\' | sed 's|\\|\/|g'

bugmenot · 2021-07-15 20:07:37 20
Remove all the characters after last space per line including it

It his example removes ' dog', last space included. Show Sample Output
This is sample output - yours may be different.
```
The quick brown fox jumps over the lazy
```
0

echo 'The quick brown fox jumps over the lazy dog' | sed 's|$.*$ .*|\1|'

bugmenot · 2021-07-15 20:01:32 16
Download screenshot or frame from YouTube video at certain timestamp

Downloads the frame of given YouTube video at 8 minutes 14 seconds. Requested format is "299", which 1080p only video.
This is sample output - yours may be different.
-1

ffmpeg -ss 8:14 -i $(youtube-dl -f 299 --get-url URL) -vframes 1 -q:v 2 out.jpg

bugmenot · 2021-07-06 10:59:49 17
Colorize grep output
This is sample output - yours may be different.
1

grep --color -E 'pattern|$' file

alikhalil · 2021-07-05 16:19:25 17
Print lines in a text file with numbers in first column higher or equal than a value

A text file contains thousands of numbers. This command prints lines were the number is greater or equal than a specified value (134000000). Show Sample Output
This is sample output - yours may be different.
```
134013941.402859
134298679.533591
134694074.478486
```
0

awk '$NF >= 134000000 {print $0}' single-column-numbers.txt

bugmenot · 2021-06-30 07:48:47 31
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Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

copy/mkdir and automatically create parent directories

The --parents option will cause cp or mkdir to automatically create the parent directory structure. $mkdir --parents /one/two/three/dir will create /one, /one/two, and /one/two/three as needed before creating dir. cp will copy files with their full directory structure into the target directory with this option. Thanks to Peter Leung at: http://linuxcommando.blogspot.com/2007/11/use-of-parents-flag-in-mkdir-and-c.html which has good examples of usage.

List files with full path

find out how much space are occuipied by files smaller than 1024K

The command gives size of all files smaller than 1024k, this information, together with disk usage, can help determin file system parameter (e.g. block size) or storage device (e.g. SSD v.s. HDD). Note if you use awk instead of "cut| dc", you easily breach maximum allowed number of records in awk.

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"

Generic shell function for modifying files in-place

Some commands (such as sed and perl) have options to support in-place editing of files, but many commands do not. This shell function enables any command to change files in place. See the sample output for many examples. The function uses plain sh syntax and works with any POSIX shell or derivative, including zsh and bash.

convert a mp4 video file to mp3 audio file (multiple files)

Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

Rename files in batch

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

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