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Extract content between the first " and the last " double quotes

Thanks to this user: https://stackoverflow.com/a/35636373/2394635 Show Sample Output
This is sample output - yours may be different.
```
checkin_resumestorevisit \"- "Online_V2.mt
```
1

s='Test "checkin_resumestorevisit \"- "Online_V2.mt" Run'; s=${s#*'"'}; s=${s%'"'*}; echo "$s"

bugmenot · 2022-01-08 16:16:18 365
Arch Linux: Always install software without asking

Adding this alias to ~/.bashrc or, better yet, the system-wide /etc/bash.bashrc (as in my setup) will make it possible to not only run pacman as any user without needing to prepend sudo but will also ensure that it always assumes that the user knows what he or she is doing. Not the best thing for large multi-user enterprise setups at all to say the least, but for home (desktop) use, this is a fantastic time-saver.
This is sample output - yours may be different.
3

alias pacman=‘sudo pacman --noconfirm’

realkstrawn93 · 2021-12-28 20:29:13 569
find packages installed from e.g. sid which are newer than those available from e.g. testing when sid is no longer present as a source repo

This is useful if you add sid, install some packages, then remove sid and want to work out which packages you installed from sid that should be removed (e.g. before an upgrade to the new stable). Alternatively you can think of this as "find installed packages that can no longer be installed."
This is sample output - yours may be different.
1

aptitude search -F '%p %v %V %O' '?narrow(?not(?archive("^[^n][^o].*$")),?version(CURRENT))' | while IFS=' ' read -r pkg ver candidate origin; do if [[ $ver == "$candidate" ]] && [[ $origin == '(installed locally)' ]]; then echo "$pkg"; fi; done

sorpigal · 2021-12-26 15:57:15 304
Display disk partition sizes

Use lsbk (list block) and jq (to manipulate a JSON on the command line) to display partition information: Show Sample Output
This is sample output - yours may be different.
```
["loop0","55.5M"]
["loop1","156M"]
["loop2","32.3M"]
["zram0","4G"]
["nvme0n1","476.9G"]
```
2

lsblk --json | jq -c '.blockdevices[]|[.name,.size]'

mikhail · 2021-12-22 22:31:07 275
Monitor memory without top or htop

It repeats a command, such as free, every five seconds and highlights the differences
This is sample output - yours may be different.
1

watch -n 5 -d '/bin/free -m'

mikhail · 2021-12-22 22:28:59 235
Find failures with journalctl

Sometimes things break. You can find the most recent errors using a combination of journalctl, along with the classic tools sort and uniq Show Sample Output
This is sample output - yours may be different.
```
898172 "/usr/bin/dockerd"
    752 "/usr/local/sbin/node_exporter"
     30 "/usr/bin/gnome-shell"
     26 "/usr/bin/cat"
     22 "/usr/libexec/gsd-media-keys"
[...]
```
1

journalctl --no-pager --since today --grep 'fail|error|fatal' --output json | jq '._EXE' | sort | uniq -c | sort --numeric --reverse --key 1

mikhail · 2021-12-22 22:27:17 212
Share a file quickly using a python web server

Raise your hand if you haven't used this at least once to share a directory quickly
This is sample output - yours may be different.
3

cd $mydir && python3 -m http.server 8888

mikhail · 2021-12-22 22:24:37 210
Apply a command on files with different names

The shell {} operator is great for this. Here's an example with three directories enclosed in {}:
This is sample output - yours may be different.
0

mkdir -p -v /home/user/tmp/{dir1,anotherdir,similardir}

mikhail · 2021-12-22 22:22:51 324
Create a progress bar over entire window until we count to 1000

https://wuseman.nr1.nu:8080/file/E8AcLVgMPZ2LSJQf/9BD8V8ADYNhR6cca/parallel_print_progress.gif Show Sample Output
This is sample output - yours may be different.
```
https://wuseman.nr1.nu:8080/file/E8AcLVgMPZ2LSJQf/9BD8V8ADYNhR6cca/parallel_print_progress.gif
```
1

seq 1000 |parallel -j30 --bar '(echo {};sleep 0.1)'

wuseman1 · 2021-12-13 11:24:50 213
Alias to list all functions loaded into bash (that don't start with _). Also shows file it's defined in.

Should run anywhere that Bash works.. Your mileage may vary. Show Sample Output
This is sample output - yours may be different.
```
cclock                       206  /home/myuser/.functions.sh
chmodd                       236  /home/myuser/.functions.sh
chmodf                       242  /home/myuser/.functions.sh
cmdfu                        41   /home/myuser/.functions.sh
command_not_found_handle     58   /etc/bash.bashrc
dequote                      148  /usr/share/bash-completion/bash_completion
dmesg_with_human_timestamps  252  /home/myuser/.functions.sh
```
-2

alias functions='shopt -s extdebug;declare -F | grep -v "declare -f _" | declare -F $(awk "{print $3}") | column -t;shopt -u extdebug'

goeltzec · 2021-11-22 06:49:36 421
Use QEMU to create a hardware dual-boot without rebooting

After downloading an ISO image, assuming you have QEMU installed, it’s possible to boot an ISO image in a virtual machine and then install that ISO from within the virtual machine directly to a physical drive, bypassing the need to reboot. Simply pass the ISO image as the -cdrom parameter, followed by “format=raw,file=/dev/sdb” (replace /dev/sdb with the drive you want to install to) as the hard drive parameter (making absolutely certain to specify the raw format, of course). Once you boot into the ISO image with QEMU, just run the installer as if it were a virtual machine — it’ll just use the physical device as an install target. After that, you’ll be able to seamlessly boot multiple distros (or even other operating systems) at once.
This is sample output - yours may be different.
2

sudo qemu-system-x86_64 -bios /usr/share/ovmf/x64/OVMF.fd -accel kvm -boot d -cdrom ubuntu-21.10-desktop-amd64.iso -drive format=raw,file=/dev/sdb -m 4096

realkstrawn93 · 2021-11-04 22:50:57 683
List all installed kernels on Ubuntu except current one

Lists all installed kernels minus the current one. This is useful to uninstall older kernels that take too much space on /boot partition. Show Sample Output
This is sample output - yours may be different.
```
linux-image-5.11.0-38-generic
linux-modules-5.11.0-38-generic
linux-modules-extra-5.11.0-38-generic
```
4

dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/$.*$-$[^0-9]\+$/\1/")"'/d;s/^[^ ]* [^ ]* $[^ ]*$.*/\1/;/[0-9]/!d'

bugmenot · 2021-10-30 22:32:29 317
Crash bash, in case you ever want to for whatever reason

This is a very hackish way to do it that I'm mainly just posting for fun, and I guess technically can more accurately be said to result in undefined behavior. What the command does is tell the shell to treat libpng like it's a shell plugin (which it's most certainly not) and attempt to install a "png_create_read" command from the library. It looks for the struct with the information about the command; since it's always the command name followed by "_struct", it'll look for a symbol called "png_create_read_struct". And it finds it, since this is the name of one of libpng's functions. But bash has no way to tell it's a function instead of a struct, so it goes ahead and parses the function's code as if it was command metadata. Inevitably, bash will attempt to dereference an invalid pointer or whatever, resulting in a segfault.
This is sample output - yours may be different.
3

enable -f /usr/lib/libpng.so png_create_read

Sparkette · 2021-10-09 05:22:52 379
Infinite loop ssh
This is sample output - yours may be different.
1

until ssh login@10.0.0.1; do echo "Nope, keep trying!"; fi; sleep 10; done

minnmass · 2021-09-29 14:53:55 998
Infinite loop ssh

Useful when you wait for a server to boot up.
This is sample output - yours may be different.
0

while true; do ssh login@10.0.0.1; if [[ $? -ne 0 ]]; then echo "Nope, keep trying!"; fi; sleep 10; done

FluffyBrick · 2021-09-29 12:54:17 320
Download SSL/TLS pem format cert from https web host
This is sample output - yours may be different.
4

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 02:37:00 213
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.
5

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

x3mboy · 2021-09-21 14:43:48 229
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
```
2

Test-NetConnection -ComputerName example.com -Port 443

EBAH · 2021-09-16 16:11:04 202
Superfast portscanner
This is sample output - yours may be different.
2

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 {})'

wuseman1 · 2021-09-14 16:15:51 228
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 16:45:20 580
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.
1

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

Negate · 2021-09-05 00:37:07 240
Banner Grabber
This is sample output - yours may be different.
1

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

wuseman1 · 2021-09-03 00:18:05 255
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 14:05:36 182
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 16:04:11 220
Store Host IP in variable
This is sample output - yours may be different.
-1

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

wuseman1 · 2021-08-10 03:48:21 219
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Backup all MySQL Databases to individual files

No need to loop when we have `xargs`. The sed command filters out the first line of `show databases` output, which is always "Database".

floating point operations in shell scripts

using bc is for sissies. dc is much better :-D Polish notation will rule the world...

Configuring proxy client on terminal without leaving password on screen or in bash_history

Prompts the user for username and password, that are then exported to http_proxy for use by wget, yum etc Default user, webproxy and port are used. Using this script prevent the cleartext user and pass being in your bash_history and on-screen

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"

Determine if a port is open with bash

For times when netcat isn't available. Will throw a Connection refused message if a port is closed. Scriptable: $ (: /dev/null && echo "OPEN" || echo "CLOSED"

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

Bind a key with a command

Now type Ctrl-l and it will list all files

Convert a SVG file to grayscale

It requires inkscape 0.46 and lxml packages

Search for a process by name

ps and grep is a dangerous combination -- grep tries to match everything on each line (thus the all too common: grep -v grep hack). ps -C doesn't use grep, it uses the process table for an exact match. Thus, you'll get an accurate list with: ps -fC sh rather finding every process with sh somewhere on the line.

Two command output

Summarize established connections after netstat output. Using tee and /dev/stderr you can send one command output to terminal before executing wc so you can summarize at the bottom of the output.

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