Update cheatsheets

tldr/$

@@ -27,3 +27,11 @@ source: https://github.com/tldr-pages/tldr.git
 - Expand with the output of `command` and run it. Same as enclosing `command` in backtics:
 
 `$({{command}})`
+
+- List how many arguments the current context has:
+
+`echo $#`
+
+- Print out a Bash array:
+
+`echo ${array[@]}`

tldr/linux/dialog

@@ -0,0 +1,21 @@
+---
+syntax: markdown
+tags: [tldr, linux]
+source: https://github.com/tldr-pages/tldr.git
+---
+# dialog
+
+> Display dialog boxes on the terminal.
+> More information: <https://manned.org/dialog>.
+
+- Display a message:
+
+`dialog --msgbox "{{Message}}" {{height}} {{width}}`
+
+- Prompt the user for text:
+
+`dialog --inputbox "{{Enter text:}}" {{8}} {{40}} 2>{{output.txt}}`
+
+- Prompt the user for a yes/no question:
+
+`dialog --yesno "{{Continue?}}" {{7}} {{40}}`