fortune for Windows Powershell

The net of law is spread so wide,
No sinner from its sweep may hide.
Its meshes are so fine and strong,
They take in every child of wrong.
O wondrous web of mystery!
Big fish alone escape from thee!
		-- James Jeffrey Roche

Included in many Linux distributions is a fun little program called fortune that prints a random, often amusing message to the screen. If you've ever wanted the same functionality in Windows PowerShell, you've come to the right place!

Installation

  1. Download fortune.txt and save it in %USERPROFILE%\Documents\WindowsPowerShell\fortune.txt
  2. Place the following in your PowerShell profile. In PowerShell, type notepad $profile to edit your profile.
    function fortune {
    	[System.IO.File]::ReadAllText((Split-Path $profile)+'\fortune.txt') -replace "`r`n", "`n" -split "`n%`n" | Get-Random
    }
    
    # Remove the line below if you do not want fortune to run when PowerShell starts
    fortune; echo ''

Using .dat files

This version is much faster on large fortune files. Use this if have a corresponding .dat file for your fortune cookie file generated by strfile. Largely untested, only works properly on UTF-8 files.

function fortune($Path) {
	if(!(Test-Path $Path)) {
		throw "File not found: $path"
	}
	
	$datfile = "$Path.dat"
	if(Test-Path $datfile) {
		$dat = New-Object "System.IO.FileStream" $datfile, 'Open', 'Read', 'Read'
		[byte[]] $dat_bytes = New-Object byte[] 8
		$seek = (Get-Random -Minimum 7 -Maximum ([int]($dat.Length / 4))) * 4
		[void] $dat.Seek($seek, 'Begin')
		[void] $dat.Read($dat_bytes, 0, 8)
		[array]::Reverse($dat_bytes) # Swap endianness
		$start = [BitConverter]::ToInt32($dat_bytes, 4)
		$end = [BitConverter]::ToInt32($dat_bytes, 0)
		$len = $end - $start - 2
		$dat.Close()

		$cookie = New-Object "System.IO.FileStream" $Path, 'Open', 'Read', 'Read'
		[byte[]] $cookie_bytes = New-Object byte[] $len
		[void] $cookie.Seek($start, 'Begin')
		[void] $cookie.Read($cookie_bytes, 0, $len)
		# If you want multiple encodings you'll have to do it yourself
		[System.Text.Encoding]::UTF8.GetString($cookie_bytes)
		$cookie.Close()
	} else {
		[System.IO.File]::ReadAllText($Path) -replace "`r`n", "`n" -split "`n%`n" | Get-Random
    }
}

Credits

fortune.txt was generated from http://fortunes.cat-v.org/openbsd/.