windows command

[Sayed, Irfan (Irfan)]

Hi All,
 
I need to execute windows system command in Ant's build.xml. I got one
sample in manual but need to know what is the exact meaning of every
line with every attribute.
 
<exec dir="${src}" executable="cmd.exe" os="Windows 2000"
output="dir.txt">
  <arg line="/c dir"/>
  </exec>
 
Can somebody please help 
 
Regards
Irfan.