How to specify lib directory for ant task? -

i'm running exec task in build this:

<target name="bar">   <exec executable="ant">     <arg value="-f"/>     <arg value="/path/to/my/build.xml"/>     <arg value="-lib"/>     <arg value="/path/to/my/libs"/>   </exec> </target> 

i don't , want replace exec task ant task:

<target name="bar">   <ant antfile="/path/to/my/build.xml"/> </target> 

however, don't know how specify lib directory in case. possible somehow?

what trying achieve, launching ant within ant in manner?

for example if need custom ant extensions, path these jars can specified @ runtime within code follows:

<taskdef resource="net/sf/antcontrib/antcontrib.properties">   <classpath>     <pathelement location="${lib.dir}/ant-contrib-0.3.jar"/>   </classpath> </taskdef> 

better again, integrate dependency management system apache ivy manage 3rd party jar dependencies.