# OS

Tips related to exploitation systems

## Install iso

### Ubuntu or debian

Use `startup disk creator` under ubuntu.

### Command line

Check what is you USB drive with `lsblk`

Unmount with `sudo umount /dev/sdb1`

Install iso with

```sh
sudo dd bs=4M if=dsl-4.4.10.iso of=/dev/sdb status=progress oflag=sync
```

## Ubuntu server

### Fix disabled ethernet

Get interface name (e.g.: _enp2s0_): `ip addr`

Edit the file `/etc/netplan/00-installer-config.yaml` and fix your interface name.

## Ubuntu desktop

Tips to set Ubuntu desktop.

### Wipe a disk without sleep

```sh
sudo systemd-inhibit shred -n 2 -zf /dev/sdX
```

`systemd-inhibit` prevent computer to sleep during commande.

### Change default terminal to Xfce terminal

Install xfce terminal with **Ubuntu software**.

Use the command : `sudo update-alternatives --config x-terminal-emulator`

### Game save folder for Gog games

FTL and Into the Breach saves are in `.local/share/` folder.

### Add desktp apps

Set your _desktop_ file in `~/.local/share/applications/`.

[Tutorial to create a desktop file](https://linuxconfig.org/how-to-create-custom-desktop-files-for-launchers-on-linux).

[Complete list of keys on freedesktop.org](https://specifications.freedesktop.org/desktop-entry-spec/desktop-entry-spec-latest.html#recognized-keys).

## Grub

`sudo update-grub`

## Install dynamic library

Tested with [box2d](https://github.com/erincatto/box2d).

### Install includes

Header files (`*.h`) must rely in a include folder, like `/usr/local/include/`. You can group headers in folders, but you have to take folders into account for preprocessing :

On your file system :

```
include
|—— hello.h
\—— box2d
	|── b2_world.h
	\—— box2d.h
```

In C++ :

```
#include <hello.h>
#include <box2d/box2d.h>
```

### Library

Compiled files (`*.a` or `*.so`, commonly generated through a buil system like `make` or `cmake`), must rely in a linked folder, like `/usr/local/lib`.

### Linking

If your static lib is named `libhello.a`, you link with the compiler flag `-lhello`.

For instance, `libbox2d.a` is linked with the flag `-lbox2d`.

## Windows and Linux

### Time clash

#### Use same time as windows
timedatectl set-local-rtc 1 --adjust-system-clock

#### Revert
timedatectl set-local-rtc 0 --adjust-system-clock