dispatcher

Powerful process forwarder (or proxy) for Windows. It can be considered as a open source, free and more powerfull alternative to chocolatey shimgen

How to use

Rename/duplicate dispatcher.exe to [something].exe. Write a [something].config file next to it to configure redirection.

Configuration file syntax is :

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <add key="PATH" value="[relative of full path to the exe you want to call]"/>
  </appSettings>
</configuration>

Download

Find all downloads in GitHub Releases

Motivation - sample usage

I use a lot of command line tool in windows (interpreters, encoders, git & related tools) All of them need to be in my PATH (that I don’t like to change). Merging them all in the same folder is a no go (.dll conflicts / overrides)

Using dispatcher.exe allows me to register only ONE directory in my Windows PATH, with very simple .exe forwarding processes to their genuine installation path.

# Current setup tree
C:\Program Files\node\bin\node.exe
C:\Program Files x86\php\bin\php.exe
D:\weird\directory\turtoisesvn\svn.exe
C:\cygwin\bin\git.exe


# I create  a single, well balanced directory
C:\dispatchedbin\

# I dispatch all binaries I want in it
C:\dispatchedbin\node.exe
C:\dispatchedbin\node.exe.config => D:\weird\directory\node-testing\node.exe

C:\dispatchedbin\php.exe
C:\dispatchedbin\php.exe.config => C:\Program Files x86\php\bin\php.exe

Advanced usage, few things to understand

• There is a fundamental difference in console applications & desktop applications for windows
• therefore dispatcher comes in 2 flavors - respectively dispatcher_cmd.exe & dispatcher_win.exe.
• You cannot spawn x64 executables located in c:\windows\system32 from a win32 application.
• therefore dispatcher.exe is available in 2 architectures : x32 & x64

Forced args

You can force additional args (injected before args that might have been sent toward [dispatched].exe

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <add key="ARGV[XXX]" value="[optional argv 0 to XXX]"/>
  </appSettings>
</configuration>

Env vars

You can define custom env var in dispatcher.config

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <!-- Mandatory -->
    <add key="PATH" value="D:\apps\System32\bash.exe"/>
    <!-- All optionals -->
    <add key="ARGV0" value="-c"/>
    <add key="ARGV1" value="/usr/sbin/sshd -D"/>
    <add key="USE_SHOWWINDOW" value="true"/>
    <add key="CWD" value="c:\my\working\dir"/>

    <add key="ENV_FOO" value="bar"/>
    <add key="ENV_OTHERTHING" value="something"/>
  </appSettings>
</configuration>

%dwd% macro

• %dwd% is replaced with the absolute path to the [dispatched].exe directory

Multiple flavor

Using the env var DISPATCHER_*NAME*_FLAVOR you can toggle multiple flavor of an exe with the same dispatcher

node.config

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>

    <add key="PATH" value="..\node-v12.22.9-win-x64\node.exe"/>
    <add key="PATH_8" value="..\node-v8.17.0-win-x64\node.exe"/>
    <add key="PATH_16" value="..\node-v16.19.0-win-x64\node.exe"/>

    <add key="ENV_NODE_PATH" value="%dwd%/node_modules"/>
  </appSettings>
</configuration>


set DISPATCHER_NODE_FLAVOR=8 # will toggle node 8
set DISPATCHER_NODE_FLAVOR=16 # will toggle node 16

DETACHED flag

When using dispatcher_win, you can use the DETACHED flag for the dispatcher NOT to wait for the child to exit.

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <add key="PATH" value="putty.exe"/>
    <add key="DETACHED" value="true"/>
  </appSettings>
</configuration>

spawn a command line app with no window (WSL bash.exe)

If you dispatch a console app (e.g. WSL bash.exe) from a desktop app (i.e. dispatch_win_x64.exe) you'll hide the window

# In my current configuration
D:\apps\wsl-init.exe (dispatch_win_x64.exe)
D:\apps\wsl-init.exe.config
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <add key="PATH" value="C:\Windows\System32\bash.exe"/>
    <add key="ARGV0" value="-c"/>
    <add key="ARGV1" value="/usr/sbin/sshd -D"/>
    <add key="USE_SHOWWINDOW" value="true"/>
  </appSettings>
</configuration>

Pre-executation command

Using the PRESTART_CMD flag make dispatcher run a command before another (useful for services).

Using dispatcher to run Windows service

Using the AS_SERVICE flag make dispatcher expose a Windows Service compliant interface. (therefore, you can use dispatcher to register any nodejs/php/whaterver script as a service. You'll have to manage the registration by yourself - see sc create,sc start, sc stop, ... APIs). Also, if needed, you can run a service in an interactive session (interact with desktop - use murrayju CreateProcessAsUser ).

When using "auto" as value for AS_SERVICE, dispatcher will use the service mode only if running as NT_AUTHORITY.

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <add key="PATH" value="node.exe"/>
    <add key="ARGV0" value="main.js"/>
    <add key="AS_SERVICE" value="true"/>

<!-- prevent execution during UWF servicing sessions ->
    <add key="UWF_SERVICING_DISABLED" value="true"/>

<!-- to run a service in interactive session -->
    <add key="AS_DESKTOP_USER" value="true"/>

  </appSettings>
</configuration>

UWF_SERVICING_DETECT

Using the AS_SERVICE or the UWF_SERVICING_DETECT flag will populate the UWF_SERVICING_ENABLED env variable with wether or not servicing mode is in progress.

Redirect output to a file (usefull for services)

Using the OUTPUT flag redirect stderr & stdout to a dedicated file. Date modifiers are available.

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <add key="PATH" value="node.exe"/>
    <add key="ARGV0" value="main.js"/>
    <add key="OUTPUT" value="%temp%\logs-%Y%-%m%-%d% %H%-%i%-%s%.log"/>
  </appSettings>
</configuration>

Service restart policy

In service mode, dispatcher will restart your process every time it exit, with an exponential (pow 2) backoff delay.

SERVICE_RESTART_ON_NETWORK_CHANGE

Dispatcher can monitor network interface status change. Use the SERVICE_RESTART_ON_NETWORK_CHANGE flag to reset the backoff delay.

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <add key="PATH" value="node.exe"/>
    <add key="ARGV0" value="main.js"/>
    <add key="AS_SERVICE" value="true"/>

    <add key="SERVICE_RESTART_ON_NETWORK_CHANGE" value="true"/>
  </appSettings>
</configuration>

Configuration lookup path

dispatcher will lookup for configurations directives in

• if existing [dispatched].config (xml file)
• if existing [dispatched].exe.config (xml file)
• all matching [dispatched_directory]/[dispatched].config.d/*.config (xml files)

Any directive defined multipled time will be overrided with the latest value

Using multiple versions of the same software

install php 5 in
C:\Program Files x86\php5.0\bin\php.exe
install php 7 in
C:\Program Files x86\php7.0\bin\php.exe

Create to dispatcher (php5.exe & php7.exe)

Make a portable binary out of any shell/script

Using dispatcher.exe is a nifty way to create portable binaries out of shell scripts (.bat,.js,.php)

How does it work

dispatcher use kernel32 Process spawn to force stdin, stdout & stderr handler to the forwarded process. Therefore, supports PIPE, Console or FILE as process handle (& all others handler). The dispatcher & the underlying process are bound to kernel32 Job group (tied together, you cannot kill one without the other). Exit code is forwarded.

Running the command is slow

If you have a fresh install of Windows, you may have to build native images to improve performance of managed applications.

Open Command Prompt as an administrator and run these commands:

%windir%\Microsoft.NET\Framework\v4.0.30319\ngen.exe executeQueuedItems
%windir%\Microsoft.NET\Framework64\v4.0.30319\ngen.exe executeQueuedItems

If this does not solve the issue, it may be the application that Dispatcher is calling itself having slowdown issues.

Tested & approved binaries (for reference)

• cmd apps : git (msysgit-1.8.4), php, node, python, svn, xpdf (pdftotext & ..), openssl, rsync, bash, gzip, tar, sed, ls, tee & co (from msysgit), ffmpeg, gsprint, 7z, ...
• desktop apps : nwjs, process explorer

Credits

• 131
• murrayju
• Code signing, courtesy of IVS Group.

Relatives/alternatives

• run.exe kinda stuff
• shimgen

Shoutbox, keywords, SEO love

background cmd, wsl bash, linux subsystem, process forward, kernel32, USE_SHOWWINDOW