main

Author: sharpchen

docs/document/Articles/docs/Setup nix-on-droid.md

@@ -26,16 +26,21 @@
 ## Init
 
 - nix-on-droid may ask for url for certain file, if the url is not accessible on your phone, download it and transfer to your phone. And replace the default url as `file:///sdcard/...`
+> remember to allow file permision for nix-on-droid.
 - type `yes` when nix prompt for downloads for first init.
 - add and update channels: 
     ```sh
-    nix-channel --add https://github.com/nix-community/home-manager/archive/release-24.05.tar.gz home-manager && nix-channel --update
+    nix-channel --add https://nixos.org/channels/nixos-unstable nixpkgs && nix-channel --add https://github.com/nix-community/home-manager/archive/master.tar.gz home-manager && nix-channel --update
     ```
     > [!TIP]
     > If you use the wrapper function mentioned above, would be like this:
     >```ps1
     >adbin -Enter 'nix-channel --add https://github.com/nix-community/home-manager/archive/release-24.05.tar.gz home-manager'
     >```
+- Update nix: default nix is out-dated, might not work with your current config like home-manager or any other.
+    ```sh
+    nix profile install nixpkgs#nix --priority 4
+    ```
 
 ## Connect to nix-on-droid
 
@@ -63,10 +68,16 @@ ssh-keygen -t rsa -b 4096 -f ssh_host_rsa_key -N "" # key is generated in pwd
 mkdir -p ~/.ssh/ && touch ~/.ssh/authorized_keys && echo <pub> >> ~/.ssh/authorized_keys
 ```
 
+> [!TIP]
+> Use this instead if you prefer pwsh, replace the pubkey name if needed.
+>```ps1
+>adbin -Enter ('mkdir -p ~/.ssh/ && touch ~/.ssh/authorized_keys && echo ''{0}'' >> ~/.ssh/authorized_keys' -f (gc ~/.ssh/id_ed25519.pub))
+>```
+
 - start ssh daemon by `sshd`
 
 ```sh
-$(which sshd) -p <port> -h <host_key> -d
+$(which sshd) -p 8080 -h ./ssh_host_rsa_key -d
 ```
 
 `-d` is essential to know whether your port is been taken or not. See details in `man sshd`.

docs/document/PowerShell/docs/Language/String.md

@@ -167,6 +167,34 @@ Use `*` to repeat a string.
 'abc' * 2 # abcabc
 ```
 
+## Grep
+
+`Select-String` is a builtin cmdlet that does the similar thing like `grep` in gnu coreutils.
+It can select one or more lines that matches the specified regex.
+
+- Grep single line from pipeline
+
+```ps1
+# -Pattern is positional
+help sls | sls -Pattern 'Position\??\s*\d'
+```
+
+- Grep multiple lines from above and below
+
+```ps1
+# include 3 lines above and 5 lines below the macthed line
+help sls | sls 'Position\??\s*\d+' -Context 3,5
+```
+
+- Grep from pipeline passed by property(`-Path`)
+
+```console
+PS ~> gci /nix/store/ -dir | sls 'roslyn'
+
+/nix/store/m4npcw66155bbi8i7ipp0bbp54wdwwlg-roslyn-ls-4.13.0-3.24577.4
+/nix/store/np6bigb7d3lvpinw0mrdvj38xi67q6sa-roslyn-ls-4.12.0-2.24422.6
+```
+
 ## String Evaluation in Interpolation
 
 ### Collection

docs/document/PowerShell/docs/Understanding Remoting.md

@@ -0,0 +1,63 @@
+# Understanding Remoting
+
+## The Protocol
+
+PowerShell uses a protocol that you might have never heard of, the *Web Services for Management(WSMan)*, which is one of the builtin *PSProvider* on Windows.
+WSMan is Windows specific feature, so as PowerShell came into the cross-platform world, Microsoft decided to support SSH which is more commonly used over industries.
+Microsoft made effort to bring SSH to Windows world, they're maintaining [a fork of SSH in github](https://github.com/PowerShell/openssh-portable)
+
+> [!NOTE]
+> `openssh` is builtin since certain version of Windows 10.
+
+## Connect to Remote
+
+No matter which protocol you use with PowerShell, it has a unified cmdlet to connect to one.
+Of course this requires PowerShell available on both sides.
+
+- Using SSH
+
+```ps1
+# login as <user> on <ip>
+Enter-PSSession -HostName <host> -UserName <user> -Port <port>
+# or use a short syntax
+Enter-PSSession -HostName <usr>@<host>
+```
+
+- Using WSMan
+
+```ps1
+# -ComputerName used instead for connection by WSMan
+Enter-PSSession -ComputerName <host> -UserName <user>
+```
+
+Optionally, you can store the session as variable instead of entering it by `New-PSSession`.
+
+```ps1
+$session = New-PSSession -HostName <host> -UserName <usr>
+```
+
+## Disconnect from Remote
+
+```ps1
+Exit-PSSession
+```
+
+## Execute Command on Remote
+
+- Execute a same command on one or more remotes.
+
+```ps1
+Invoke-Command -HostName <host1>[,<host2>, ...] -UserName <usr> -ScriptBlock { <cmd> }
+```
+
+- Execute on a persistent session
+
+```ps1
+$session = New-PSSession -HostName <host> -UserName <usr>
+icm -Session $s -ScriptBlock { <cmd> }
+```
+
+> [!NOTE]
+> `Invoke-Command` returns deserialized object converted from transferred xml from remotes, it reflects data on remote only.
+> You should only aggregate format it without mutating the values.
+> `Enter-Session` does enter a PowerShell session, so it operates on a real PowerShell instance just like what you can do with SSH.

docs/document/PowerShell/docs/What to Learn for New cmdlet.md

@@ -0,0 +1,46 @@
+# What to Learn from New cmdlet
+
+## Find Positional Parameter
+
+Positional parameter matters for understanding the examples listed on documentations since the example might elide parameter name.
+We can take advantages of `Get-Help` and `Select-String` to capture those parameters that have a explicit order.
+The `-Context` includes 3 lines above and 5 lines below the display the whole info of the parameter.
+
+```ps1
+help <cmd> | sls 'Position\??\s*\d' -Context 3,5
+```
+
+The example usage is exactly what we have used here, the `Select-String`.
+It has two positional parameters, `-Pattern` and `-Path`.
+So in the previous example, the `-Pattern` was omitted.
+
+```console
+$ help sls | sls 'Position\??\s*\d+' -Context 3,5
+
+      -Path <string[]>
+
+          Required?                    true
+>         Position?                    1
+          Accept pipeline input?       true (ByPropertyName)
+          Parameter set name           File, FileRaw
+          Aliases                      None
+          Dynamic?                     false
+          Accept wildcard characters?  false
+      -Pattern <string[]>
+
+          Required?                    true
+>         Position?                    0
+          Accept pipeline input?       false
+          Parameter set name           (All)
+          Aliases                      None
+          Dynamic?                     false
+          Accept wildcard characters?  false
+```
+
+## Find Parameters Accepts Pipeline
+
+Similar to finding position parameter.
+
+```ps1
+help <cmd> | sls 'Accept pipeline input\??\s*true.*$' -Context 5,4
+```