Add a line to System variables path with batch file

IF you want the simplest solution you can use the SETX command in Windows 7:

SETX PATH "%PATH%;C:\New Added Folder"

PS1: Use the -M parameter if you want the SETX command to perform the changes on HKLM key.

PS2: The changes are PERMANENT but you need to restart user session or console.

If you want a a little thing more professional then you can use my utility PATHS wrote in Ruby, and i made an executable for Windows.

PATHS.EXE

http://exoshare.com/download.php?uid=1TKIOMR6

Options:

/? (or) -help | Show this info.

-l (or) -list | List the entries.

-c (or) -clean | Clean duplicates and invalid directories in the paths.

-r (or) -reset | Reset the paths to the Windows defaults.

-a (or) -add | Add a entry.

-d (or) -del | Delete a entry.

-add -current | Force adding a entry into the current user path.

-add -local | Force adding a entry into the local machine path.

Examples:

PATHS -l [+] Indexes all the entries.

PATHS -a "C:\Folder" [+] Adds a entry into the local path.

PATHS -a current "C:\Folder" [+] Adds a entry into the current user path.

PATHS -d "3" [+] Deletes the 3rd entry of the indexed list.

PATHS -d "C:\Folder" [+] Deletes a entry.

PATHS.RB

require 'win32/registry'
require 'rainbow'

# PATHS v0.1
#
# By Elektro H@cker


# Description:
# -----------
# This is a tool to manage the windows PATH enviroment.


exit if Object.const_defined?(:Ocra)


def logo()
  print "
   PATHS v0.1

   By Elektro H@cker

".foreground(:white)
end


def help()
  print '

   Options:

   /? (or) -help  | Show this info.

   -l (or) -list  | List the entries.

   -c (or) -clean | Clean duplicates and invalid directories in the paths.

   -r (or) -reset | Reset the paths to the Windows defaults.

   -a (or) -add   | Add a entry.

   -d (or) -del   | Delete a entry.

   -add -current  | Force adding a entry into the current user path.

   -add -local    | Force adding a entry into the local machine path.



   Examples:

   PATHS -l
   [+] Indexes all the entries.

   PATHS -a "C:\Folder"
   [+] Adds a entry into the local path.

   PATHS -a current "C:\Folder"
   [+] Adds a entry into the current user path.

   PATHS -d "3"
   [+] Deletes the 3rd entry of the indexed list.

   PATHS -d "C:\Folder"
   [+] Deletes a entry.

  '
  Process.exit
end


def error(kind)
  print "[+] ERROR"
  if kind == "pos"      then print "\n    Index #{ARGV[1]} is out of range, only #{$pos} entries.\n" end
  if kind == "notfound" then print "\n    Directory \"#{ARGV[1]}\" not found on PATH.\n" end


  Process.exit
end


def args()
  if ARGV.empty?                                   then get_paths("visible") end
  if ARGV[0] == "/?"    or ARGV[0] =~ /^-help$/i   then help()               end  
  if ARGV[0] =~ /^-l$/i or ARGV[0] =~ /^-list$/i   then get_paths("visible") end
  if ARGV[0] =~ /^-c$/i or ARGV[0] =~ /^-clean$/i  then clean_path()         end    
  if ARGV[0] =~ /^-d$/i or ARGV[0] =~ /^-del$/i    then del_path()           end
  if ARGV[0] =~ /^-a$/i or ARGV[0] =~ /^-add$/i    then add_path()           end
  if ARGV[0] =~ /^-r$/i or ARGV[0] =~ /^-reset$/i  then reset_path()         end
end


def get_paths(visibility)

  $pos = 0

  # HKCU path
  if not visibility == "hidden" then puts "\n   [+] Current User PATH:\n\n" end
  Win32::Registry::HKEY_CURRENT_USER.open('Environment') do |reg|
    for dir in reg['Path', Win32::Registry::REG_SZ].split(";").sort do
      $pos = $pos+1
      dir = dir.gsub(/^PATH=/, "")
      instance_variable_set "@_#{$pos}", dir + "?CURRENT_USER"
      if not File.directory? dir then invalid = "(Directory doesn't exist)".foreground(:red).bright else invalid ="" end
      if not visibility == "hidden"
        if $pos < 10 then puts "    #{$pos.to_s} = #{dir} #{invalid}" else puts "    #{$pos.to_s}= #{dir} #{invalid}"end
      end
    end
  end

  # HKLM path
  if not visibility == "hidden" then puts "\n\n   [+] Local Machine PATH:\n\n" end
  Win32::Registry::HKEY_LOCAL_MACHINE.open('SYSTEM\CurrentControlSet\Control\Session Manager\Environment') do |reg|
    for dir in reg['Path', Win32::Registry::REG_SZ].split(";").sort do
      $pos = $pos+1
      dir = dir.gsub(/^PATH=/, "")
      instance_variable_set "@_#{$pos}", dir + "?LOCAL_MACHINE"
      if not File.directory? dir then invalid = "(Directory doesn't exist)".foreground(:red).bright else invalid ="" end
      if not visibility == "hidden"
        if $pos < 10 then puts "    #{$pos.to_s} = #{dir} #{invalid}" else puts "    #{$pos.to_s}= #{dir} #{invalid}"end
      end
    end
  end
  if not visibility == "hidden" then Process.exit end
  $max_pos = $pos

end


def add_path()

  if ARGV[1] =~ /^-current$/ then key = "current" else key = "local" end

  # HKCU path
  if key == "current"
    Win32::Registry::HKEY_CURRENT_USER.open('Environment', Win32::Registry::KEY_ALL_ACCESS) do |reg|
      value = reg['Path']
      reg.write('Path', Win32::Registry::REG_SZ, "#{value};#{ARGV.last}")
      puts "[+] Entry added in User PATH: #{ARGV.last}"
    end
  end

  # HKLM path
  if key == "local"
    Win32::Registry::HKEY_LOCAL_MACHINE.open('SYSTEM\CurrentControlSet\Control\Session Manager\Environment', Win32::Registry::KEY_ALL_ACCESS) do |reg|
      value = reg['Path']
      reg.write('Path', Win32::Registry::REG_SZ, "#{value};#{ARGV.last}")
      puts "[+] Entry added in Local PATH: #{ARGV.last}"
    end
  end

end


def del_path()

    get_paths("hidden")
    final_path = ""
    found      = 0
    notfound   = 0

  if ARGV[1] =~ /^[1-9]+$/

    choose     = instance_variable_get "@_#{ARGV[1]}"

    if ARGV[1].to_i > $max_pos.to_i then error("pos") end

    # HKCU PATH index deletion
    if choose["?CURRENT_USER"]
      Win32::Registry::HKEY_CURRENT_USER.open('Environment', Win32::Registry::KEY_ALL_ACCESS) do |reg|
        value = reg['Path']
        for dir in reg['Path', Win32::Registry::REG_SZ].split(";").sort do
          if not dir == choose.split("?").first then final_path << ";" + dir end
        end
        reg.write('Path', Win32::Registry::REG_SZ, final_path[1..-1])
      end
      puts "[+] Entry deleted in User PATH: #{choose.split("?").first}"
    end

    # HKLM PATH index deletion
    if choose["?LOCAL_MACHINE"]
      Win32::Registry::HKEY_LOCAL_MACHINE.open('SYSTEM\CurrentControlSet\Control\Session Manager\Environment', Win32::Registry::KEY_ALL_ACCESS) do |reg|
        value = reg['Path']
        for dir in reg['Path', Win32::Registry::REG_SZ].split(";").sort do
          if not dir == choose.split("?").first then final_path << ";" + dir end
        end
        reg.write('Path', Win32::Registry::REG_SZ, final_path[1..-1])
      end
      puts "[+] Entry deleted in Local PATH: #{choose.split("?").first}"
    end

  elsif

    # HKCU PATH str deletion
      Win32::Registry::HKEY_CURRENT_USER.open('Environment', Win32::Registry::KEY_ALL_ACCESS) do |reg|
        value = reg['Path']
        for dir in reg['Path', Win32::Registry::REG_SZ].split(";").sort do
          if not dir =~ /^#{Regexp.escape(ARGV[1])}$/i then final_path << ";" + dir else found = "yes" end
        end
        reg.write('Path', Win32::Registry::REG_SZ, final_path[1..-1])
        if found == "yes" then puts "[+] Entry deleted in User PATH: #{ARGV[1]}" else notfound = 1 end
      end

    # HKLM PATH str deletion
      final_path = ""
      found = ""
      Win32::Registry::HKEY_LOCAL_MACHINE.open('SYSTEM\CurrentControlSet\Control\Session Manager\Environment', Win32::Registry::KEY_ALL_ACCESS) do |reg|
        value = reg['Path']
        for dir in reg['Path', Win32::Registry::REG_SZ].split(";").sort do
          if not dir =~ /^#{Regexp.escape(ARGV[1])}$/i then final_path << ";" + dir else found = "yes" end
        end
        reg.write('Path', Win32::Registry::REG_SZ, final_path[1..-1])
        if found == "yes" then puts "[+] Entry deleted in Local PATH: #{ARGV[1]}" else notfound = notfound+1 end
        if notfound == 2 then error("notfound") end
      end

    end

end


def reset_path()
  Win32::Registry::HKEY_CURRENT_USER.open('Environment', Win32::Registry::KEY_ALL_ACCESS) do |reg| reg.write('Path', Win32::Registry::REG_SZ, 'C:\Windows;C:\Windows\system32;C:\Windows\System32\Wbem;C:\Windows\syswow64') end
  Win32::Registry::HKEY_LOCAL_MACHINE.open('SYSTEM\CurrentControlSet\Control\Session Manager\Environment', Win32::Registry::KEY_ALL_ACCESS) do |reg| reg.write('Path', Win32::Registry::REG_SZ, 'C:\Windows;C:\Windows\system32;C:\Windows\System32\Wbem;C:\Windows\syswow64') end
  puts "[+] PATH restored to Windows defaults."
end


def clean_path()

  puts "\n[+] Searching invalid or duplicated entries in the PATH...\n\n"

  # HKCU PATH
  final_path = ""
  Win32::Registry::HKEY_CURRENT_USER.open('Environment', Win32::Registry::KEY_ALL_ACCESS) do |reg|
    value = reg['Path']
    for dir in reg['Path', Win32::Registry::REG_SZ].split(";").sort do
      if File.directory? dir and not final_path[/#{Regexp.escape(dir)}$/i] then final_path << ";" + dir else puts "[+] Entry deleted in User PATH: #{dir}" end
    end
    reg.write('Path', Win32::Registry::REG_SZ, final_path[1..-1])
  end

  # HKLM PATH
  final_path = ""
  Win32::Registry::HKEY_LOCAL_MACHINE.open('SYSTEM\CurrentControlSet\Control\Session Manager\Environment', Win32::Registry::KEY_ALL_ACCESS) do |reg|
    value = reg['Path']
    for dir in reg['Path', Win32::Registry::REG_SZ].split(";").sort do
      if File.directory? dir and not final_path[/#{Regexp.escape(dir)}$/i] then final_path << ";" + dir else puts "[+] Entry deleted in Local PATH: #{dir}" end
    end
    reg.write('Path', Win32::Registry::REG_SZ, final_path[1..-1])
  end

  puts "\n[+] PATH is cleaned.\n\n"

end


logo()
args()


Process.exit