Error when trying to list Metadata

[tgentet-obrien]

Hey,

I keep on getting an error when trying to run this on a SF instance:

BUILD FAILED
/Users/timothygentet-obrien/sf_ant/generateXML/GeneratePackage_xml.xml:211: The following error occurred while executing this line:
/Users/timothygentet-obrien/sf_ant/generateXML/GeneratePackage_xml.xml:157: The following error occurred while executing this line:
/Users/timothygentet-obrien/sf_ant/generateXML/GeneratePackage_xml.xml:81: Problem: failed to create task or type antlib:com.salesforce:listMetadata
Cause: The name is undefined.
Action: Check the spelling.
Action: Check that any custom tasks/types have been declared.
Action: Check that any <presetdef>/<macrodef> declarations have taken place.
No types or tasks have been defined in this namespace yet

This appears to be an antlib declaration. 
Action: Check that the implementing library exists in one of:
        -/Users/timothygentet-obrien/Applications/ant/lib
        -/Users/timothygentet-obrien/.ant/lib
        -a directory added on the command line with the -lib argument


Total time: 0 seconds

Could it be because I am using a Mac?

[JitendraZaa]

Can you confirm if Salesforce Metadata jar file is in path ? It seems searching for Metadata tool from Salesforce

[sghparam]

I am getting the same error...all the config is as per instructions...

[JitendraZaa]

Please make sure Metadata API jar file from Salesforce is in class path.

[ghost]

Can you please suggest how to dynamically generate package.xml based on the commits in github by passing commit id?

[FeiyangGao]

I met the same question, I put the ant-salesforce.jar into %ant_home%/lib, then, I can run this program.