Add initial Windows guide

Signed-off-by: Jason T. Greene <jason.greene@redhat.com>

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diff --git a/docs/tutorials/podman-for-windows.md b/docs/tutorials/podman-for-windows.md
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+![PODMAN logo](../../logo/podman-logo-source.svg)
+
+Podman for Windows
+==================
+
+While "containers are Linux," Podman also runs on Mac and Windows, where it
+provides a native CLI and embeds a guest Linux system to launch your
+containers. This guest is referred to as a Podman machine and is managed with
+the `podman machine` command. On Windows, each Podman machine is backed by a
+virtualized Windows System for Linux (WSLv2) distribution. The podman command
+can be run directly from your Windows PowerShell (or CMD) prompt, where it
+remotely communicates with the podman service running in the WSL environment.
+Alternatively, you can access Podman directly from the WSL instance if you
+prefer a Linux prompt and Linux tooling. In addition to command-line access,
+Podman also listens for Docker API clients, supporting direct usage of
+Docker-based tools and programmatic access from your language of choice.
+
+Prerequisites
+-------------
+
+Since Podman uses WSL, you need a recent release of Windows 10 or Windows 11.
+On x64, WSL requires build 18362 or later, and 19041 or later is required for
+arm64 systems. Internally, WSL uses virtualization, so your system must
+support and have hardware virtualization enabled. If you are running Windows
+on a VM, you must have a VM that supports nested virtualization.
+
+It is also recommended to install the modern "Windows Terminal," which
+provides a superior user experience to the standard PowerShell and CMD
+prompts, as well as a WSL prompt, should you want it.
+
+You can install it by searching the Windows Store or by running the following
+`winget` command:
+
+`winget install Microsoft.WindowsTerminal`
+
+
+Installing Podman
+-----------------
+
+Installing the Windows Podman client begins by downloading the Podman Windows
+installer. The Windows installer is built with each Podman release and can be
+downloaded from the official
+ [Github release page](https://github.com/containers/podman/releases). The
+Windows installer file is named podman-v.#.#.#.msi, where the # symbols
+represent the version number of Podman. Be sure to download a 4.1 or later
+release for the capabilities discussed in this guide.
+
+![Installing Podman 4.1.0](podman-win-install.jpg)
+
+Once downloaded, simply run the MSI file, and relaunch a new terminal. After
+this point, podman.exe will be present on your PATH, and you will be able to run
+the `podman machine init` command to create your first machine.
+
+`PS C:\Users\User> podman machine init`
+
+Automatic WSL Installation
+--------------------------
+
+If WSL has not been installed on your system, the first machine init command
+will prompt a dialog to begin an automated install. If accepted, this process
+will install the necessary Windows components, restart the system, and after
+login, relaunch the machine creation process in a terminal window. Be sure to
+wait a minute or two for the relaunch to occur, as Windows has a delay before
+executing startup items. Alternatively, you can decline automatic installation
+and install WSL manually. However, this will require additional download and
+setup time.
+
+Machine Init Process
+--------------------
+
+After WSL is installed, the init command will install a minimal installation
+of Fedora, customizing it to run podman.
+
+```
+PS C:\Users\User> podman machine init
+Extracting compressed file
+Importing operating system into WSL (this may take 5+ minutes on a new WSL install)...
+Installing packages (this will take a while)...
+Complete!
+Configuring system...
+Generating public/private ed25519 key pair.
+Your identification has been saved in podman-machine-default
+Your public key has been saved in podman-machine-default.pub
+The key fingerprint is:
+SHA256:RGTGg2Q/LX7ijN+mzu8+BzcS3cEWP6Hir6pYllJtceA root@WINPC
+Machine init complete
+To start your machine run:
+
+        podman machine start
+```
+
+
+Starting Machine
+----------------
+
+After the machine init process completes, it can then be started and stopped
+as desired:
+
+```
+PS C:\Users\User> podman machine start
+
+Starting machine "podman-machine-default"
+
+This machine is currently configured in rootless mode. If your containers
+require root permissions (e.g. ports < 1024), or if you run into compatibility
+issues with non-podman clients, you can switch using the following command:
+
+        podman machine set --rootful
+
+API forwarding listening on: npipe:////./pipe/docker_engine
+
+Docker API clients default to this address. You do not need to set DOCKER_HOST.
+Machine "podman-machine-default" started successfully
+```
+
+First Podman Command
+--------------------
+
+From this point on, podman commands operate similarly to how they would on
+Linux.
+
+For a quick working example with a small image, you can run the Linux date
+command on PowerShell.
+
+```
+PS C:\Users\User> podman run ubi8-micro date
+Thu May 5 21:56:42 UTC 2022
+```
+
+Port Forwarding
+---------------
+
+Port forwarding also works as expected; ports will be bound against localhost
+(127.0.0.1). Note: When running as rootless (the default), you must use a port
+greater than 1023. See the Rooftull and Rootless section for more details.
+
+To launch httpd, you can run:
+
+```
+PS C:\Users\User> podman run --rm -d -p 8080:80 --name httpd docker.io/library/httpd
+f708641300564a6caf90c145e64cd852e76f77f6a41699478bb83a162dceada9
+```
+
+A curl command against localhost on the PowerShell prompt will return a
+successful HTTP response:
+
+```
+PS C:\Users\User> curl http://localhost:8080/ -UseBasicParsing
+
+StatusCode : 200
+StatusDescription : OK
+Content : <html><body><h1>It works!</h1></body></html>
+```
+
+As with Linux, to stop, run:
+
+`podman stop httpd`
+
+
+Using API Forwarding
+--------------------
+
+API forwarding allows Docker API tools and clients to use podman as if it was
+Docker. Provided there is no other service listening on the Docker API pipe;
+no special settings will be required.
+
+```
+PS C:\Users\User> .\docker.exe run -it fedora echo "Hello Podman!"
+Hello Podman!
+```
+
+Otherwise, after starting the machine, you will be notified of an environment
+variable you can set for tools to point to podman. Alternatively, you can shut
+down both the conflicting service and podman, then finally run `podman machine
+start` to restart, which should grab the Docker API address.
+
+
+```
+Another process was listening on the default Docker API pipe address.
+You can still connect Docker API clients by setting DOCKER HOST using the
+following PowerShell command in your terminal session:
+
+        $Env:DOCKER_HOST = 'npipe:////./pipe/podman-machine-default'
+
+Or in a classic CMD prompt:
+
+        set DOCKER_HOST = 'npipe:////./pipe/podman-machine-default'
+
+Alternatively, terminate the other process and restart podman machine.
+Machine "podman-machine-default" started successfully
+
+PS C:\Users\User> $Env:DOCKER_HOST = 'npipe:////./pipe/podman-machine-default'
+PS C:\Users\User>.\docker.exe version --format '{{(index .Server.Components 0).Name}}'
+Podman Engine
+```
+
+Rootfull & Rootless
+-------------------
+
+On the embedded WSL Linux distro, podman can either be run under the root user
+(rootful) or a non-privileged user (rootless). For behavioral consistency with
+Podman on Linux, rootless is the default. Note: Rootfull and Rootless
+containers are distinct and isolated from one another. Podman commands against
+one (e.g., podman ps) will not represent results/state for the other.
+
+While most containers run fine in a rootless setting, you may find a case
+where the container only functions with root privileges. If this is the case,
+you can switch the machine to rootful by stopping it and using the set
+command:
+
+```
+podman machine stop
+podman machine set --rootful
+```
+
+To restore rootless execution, set rootful to false:
+
+```
+Podman machine stop
+Podman machine set --rootful=false
+```
+
+Another case in which you may wish to use rootful execution is binding a port
+less than 1024. However, future versions of podman will likely drop this to a
+lower number to improve compatibility with defaults on system port services (such
+as MySQL)
+
+Volume Mounting
+---------------
+
+New in Podman v4.1 is the ability to perform volume mounts from Windows paths into a
+Linux container. This supports several notation schemes, including:
+
+Windows Style Paths:
+
+`podman run -it c:\Users\User\myfolder:/myfolder ubi8-micro ls /myfolder`
+
+Unixy Windows Paths:
+
+`podman run -it /c/Users/User/myfolder:/myfolder ubi8-micro ls /myfolder`
+
+Linux paths local to the WSL filesystem:
+
+`podman run -it /var/myfolder:/myfolder ubi-micro ls /myfolder`
+
+All of the above conventions work, whether running on a Windows prompt or the
+WSL Linux shell. Although when using Windows paths on Linux, appropriately quote
+or escape the Windows path portion of the argument.
+
+
+Listing Podman Machine(s)
+-------------------------
+
+To list the available podman machine instances and their current resource
+usage, use the `podman machine ls` command:
+
+```
+PS C:\Users\User> podman machine ls
+
+
+NAME                    VM TYPE     CREATED      LAST UP            CPUS        MEMORY      DISK SIZE
+podman-machine-default  wsl         2 hours ago  Currently running  4           331.1MB     768MB
+```
+
+Since WSL shares the same virtual machine and Linux kernel across multiple
+distributions, the CPU and Memory values represent the total resources shared
+across running systems. The opposite applies to the Disk value. It is
+independent and represents the amount of storage for each individual
+distribution.
+
+
+Accessing the Podman Linux Environment
+--------------------------------------
+
+While using the podman.exe client on the Windows environment provides a
+seamless native experience supporting the usage of local desktop tools and
+APIs, there are a few scenarios in which you may wish to access the Linux
+environment:
+
++ Updating to the latest stable packages on the embedded Fedora instance
++ Using Linux development tools directly
++ Using a workflow that relies on EXT4 filesystem performance or behavior
+  semantics
+
+There are three mechanisms to access the embedded WSL distribution:
+1. SSH using `podman machine ssh`
+2. WSL command on the Windows PowerShell prompt
+3. Windows Terminal Integration
+
+### Using SSH
+
+SSH access provides a similar experience as Podman on Mac. It immediately
+drops you into the appropriate user based on your machine's rootful/rootless
+configuration (root in the former, 'user' in the latter). The --username
+option can be used to override with a specific user.
+
+An example task using SSH is updating your Linux environment to pull down the
+latest OS bugfixes:
+
+`podman machine ssh sudo dnf upgrade -y`
+
+### Using the WSL Command
+
+The `wsl` command provides direct access to the Linux system but enters the
+shell as root first. This is due to design limitations of WSL, where running
+systemd (Linux's system services) requires the usage of a privileged process
+namespace.
+
+Unless you have no other distributions of WSL installed, it's recommended to
+use the `-d` option with the name of your podman machine (podman-machine-default
+is the default)
+
+```
+PS C:\Users\User> wsl -d podman-machine-default
+```
+
+You will be automatically entered into a nested process namespace where
+systemd is running. If you need to access the parent namespace, hit `ctrl-d`
+or type exit. This also means to log out, you need to exit twice.
+
+```
+[root@WINPC /]# podman --version
+podman version 4.1.0
+```
+
+
+To access commands as the non-privileged user (rootless podman), you must
+first type `su user`. Alternatively, you can prefix the `wsl` command to use the
+special `enterns`:
+
+```
+wsl -d podman-machine-default enterns su user
+[user@WINPC /]$ id
+uid=1000(user) gid=1000(user) groups=1000(user),10(wheel)
+```
+
+Likewise, running commands as root without entering a prompt should also be
+prefixed with `enterns`.
+
+`wsl -d podman-machine-default enterns systemctl status`
+
+Accessing the WSL instance as a specific user using `wsl -u` or using inline
+commands without `enterns` is not recommended since commands will execute
+against the incorrect namespace.
+
+### Using Windows Terminal Integration
+
+Entering WSL as root is a 2-click operation. Simply click the drop-down tag,
+and pick 'podman-machine-default,' where you will be entered directly as root.
+
+![Using WSL in Windows Terminal](podman-wsl-term.jpg)
+
+As before, to switch to a non-privileged user for rootless podman commands,
+type `su user`.
+
+```
+[root@WINPC /]# su user
+[user@WINPC /]$ podman info --format '{{.Store.RunRoot}}'
+/run/user/1000/containers
+```
+
+Stopping a Podman Machine
+-------------------------
+
+To stop a running podman machine, use the `podman machine stop` command:
+
+```
+PS C:\Users\User> podman machine stop
+Machine "podman-machine-default" stopped successfully
+```
+
+Removing a Podman Machine
+-------------------------
+
+To remove a machine, use the `podman machine rm` command:
+
+```
+PS C:\Users\User> podman machine rm
+
+The following files will be deleted:
+
+C:\Users\User\.ssh\podman-machine-default
+C:\Users\User\.ssh\podman-machine-default.pub
+C:\Users\User\.local\share\containers\podman\machine\wsl\podman-machine-default_fedora-35-x86_64.tar
+C:\Users\User\.config\containers\podman\machine\wsl\podman-machine-default.json
+C:\Users\User\.local\share\containers\podman\machine\wsl\wsldist\podman-machine-default
+
+
+Are you sure you want to continue? [y/N] y
+```
+
+
+
+Troubleshooting
+---------------
+
+Recovering from a failed auto-installation of WSL
+
+If auto-install fails and retrying is unsuccessful, you can attempt to reset
+your WSL system state and perform a manual WSL installation using the `wsl
+--install command`. To do so, perform the following steps:
+
+1. Launch PowerShell as administrator
+   ```
+   Start-Process powershell -Verb RunAs
+   ```
+2. Disable WSL Features
+   ```
+   dism.exe /online /disable-feature /featurename:Microsoft-Windows-Subsystem-Linux /norestart
+   dism.exe /online /enable-feature /featurename:VirtualMachinePlatform /norestart
+   ```
+3. Reboot
+4. Run manual WSL install
+   ```
+   wsl --install
+   ```
+5. Continue with podman machine init
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