The shellCommand object contains the results from a command line process.
On Microsoft Windows platforms, the shell command starts, but we cannot get output or status from the shell command. See com.ibm.di.function.ExecuteCommand in the Javadocs for available methods.
For example:
var cmd = system.shellCommand ("/bin/ls -l"); if ( cmd.failed() ) { task.logmsg ( "Command failed: " + cmd.getError()); } else { task.logmsg ( cmd.getOutputBuffer() ); }