Setting PATH environment variable on ant build.xml works on cygwin but not on cmd or PowerShell - powershell

Question

I was trying to set PATH enviroment variable on an ant build.xml through this answer.
It works on cygwin but not on cmd or PowerShell.
Some information:
Apache Ant 1.6.5 (I know there is a newer version (1.8.4), but for internal reasons I have to use this older version)
Powershell v2.0
cmd v6.1.7601
cygwin 2.774
Windows 7

Answer 1

You may need to use the exec task a little differently on Windows/cmd environments.
Let's use the windows command set as an example. set will print environment variables. A normal exec task running a set command might look like:
<exec executable="set" outputproperty="set.output">
<env key="MY_VAR" value="MY_VAL"/>
<echo message="${set.output}"/>
</exec>
But using this form of the exec task should throw an IOException: The system cannont find the file specified.
When running ant under windows cmd shell, the exec task can also be invoked via cmd, like this:
<exec executable="cmd" outputproperty="set.output">
<arg line="/c set"/>
<env key="MY_VAR" value="MY_VAL"/>
<echo message="${set.output}"/>
</exec>
This is the equivalent command; the actual command executed is cmd /c set, which is running set in a cmd sub-process.
The reason why this is necessary is only a little complicated and is due to the way that the commands are located by Win32 ::CreateProcess. The ant exec docs briefly explain this.
Note that I haven't tried either of these using PowerShell, so I have no experience which, if either, will work.
In my own ant build scripts I typically have two versions of each target that require special handling for windows platforms, with an isWindows test that looks like this:
<target name="check-windows">
<condition property="isWindows">
<os family="windows"/>
</condition>
</target>
Then I can switch between versions of the same task using:
<target name="my-target-notwindows" depends="check-windows" unless="isWindows>
...
</target>
<target name="my-target-windows" depends="check-windows" if="isWindows>
...
</target>
<target name="my-target" depends="my-target-notwindows,my-target-windows">
...
</target>

Answer 2

Unfortunatelly was an ant bug related to 1.6.5 version. I was able to update to 1.8.4 and everything works fine.