Windows Script Host
The Microsoft Windows Script Host (WSH) is an automation technology for Microsoft Windows operating systems that provides scripting abilities comparable to batch files, but with a wider range of supported features. It was originally called Windows Scripting Host, but was renamed for the second release.
It is language-independent in that it can make use of different Active Scripting language engines. By default, it interprets and runs plain-text JScript (.JS and .JSE files) and VBScript (.VBS and .VBE files).
Users can install different scripting engines to enable them to script in other languages, for instance PerlScript. The language independent filename extension WSF can also be used. The advantage of the Windows Script File (.WSF) is that it allows the user to use a combination of scripting languages within a single file.
Windows Script Host is distributed and installed by default on Windows 98 and later versions of Windows. It is also installed if Internet Explorer 5 (or a later version) is installed. Beginning with Windows 2000, the Windows Script Host became available for use with user login scripts.
Windows Script Host may be used for a variety of purposes, including logon scripts, administration and general automation. Microsoft describes it as an administration tool. WSH provides an environment for scripts to run – it invokes the appropriate script engine and provides a set of services and objects for the script to work with. These scripts may be run in either GUI mode (WScript.exe) or command line mode (CScript.exe) offering flexibility to the user for interactive or non-interactive scripts. WSH implements an object model which exposes a set of Component Object Model (COM) interfaces.
The first example is very simple; it shows some VBScript which uses the root WSH COM object "WScript" to display a message with an 'OK' button. Upon launching this script the CScript or WScript engine would be called and the runtime environment provided.
Content of a file
WScript.Echo "Hello world" WScript.Quit
WSH programming can also use the JScript language.
Content of a file
WSH.Echo("Hello world"); WSH.Quit();
Content of a file
<job> <script language="VBScript"> MsgBox "hello world (from vb)" </script> <script language="JScript"> WSH.echo("hello world (from js)"); </script> </job>
Windows applications and processes may be automated using a script in Windows Script Host. Viruses and malware could be written to exploit this ability. Thus, some suggest disabling it for security reasons. Alternatively, antivirus programs may offer features to control .vbs and other scripts which run in the WSH environment.
Since version 5.6 of WSH, scripts can be digitally signed programmatically using the Scripting.Signer object in a script itself, provided a valid certificate is present on the system. Alternatively, the signcode tool from the Platform SDK, which has been extended to support WSH filetypes, may be used at the command line.
By using Software Restriction Policies introduced with Windows XP, a system may be configured to execute only those scripts which have been digitally signed, thus preventing the execution of untrusted scripts.
Available scripting engines
|Name||Language||File extensions||Availability||Produced By||Status||Date||Notes|
|VBScript||Microsoft Visual Basic, Scripting Edition||.vbs||Installed by default||Microsoft||default install||1999|
|JScript||Microsoft JScript||.js||Installed by default||Microsoft||default install||1999|
|PerlScript||Perl||.pls||with ActiveState Perl||ActiveState||Open source||1999|
|ooRexxScript||REXX||.rxs||with Open Object Rexx||Open Object Rexx team||Open source|
|PythonScript||Python||.pys||SourceForge||The Pywin32 project||Open source|
|TclScript||Tcl/Tk||.tcls||SourceForge||ActiveState or third party||Open source|
|ActivePHPScript||PHP||.phps||with PHP||PHP team||Open source|
|RubyScript||Ruby||.rbs||with Ruby||Ruby team||Open source|
|Object REXX engine||Object REXX||with IBM Object REXX||IBM||Commercial||2002|
|Delphi scripting engine||Delphi||In some Delphi distributions or resource kits||Commercial||2003|
|Windows version||Shipped with WSH version||Last redistributable version|
|Windows 95||None (separate redistributable)||5.6|
|Windows NT 4.0||None (separate redistributable)||5.6|
|Windows 2000||2.0 (also termed WSH 5.1)||5.7|
|Windows Me||2.0 (also termed WSH 5.1)||5.6|
|Windows XP, Windows Server 2003||5.6||5.7|
|Windows Vista, Windows Server 2008, Windows XP SP3||5.7||Not applicable|
|Windows 7, Windows Server 2008 R2||5.8||Not applicable|
|Windows 8, Windows Server 2012||5.8||Not applicable|
The redistributable version of WSH version 5.6 can be installed on Windows 95/98/Me and Windows NT 4.0/2000. WSH 5.7 is downloadable for Windows 2000, Windows XP and Windows Server 2003. Recently, redistributable versions for older operating systems (Windows 9x and Windows NT 4.0) are no longer available from the Microsoft Download Center.
As of Windows XP Service Pack 3, release 5.7 is not needed as it is included.
- WSH Primer on Microsoft TechNet – Get started with WSH
- WSH home at MSDN
- WSH Reference
- Release notes for Windows Script 5.7
- Console WSH Shell - a third-party shell for WSH and VBScript