[JSch-users] SSH exec hangs on HP Unix

[Guy <guy...@gm...>]

Hi all,

i am using jsch-0.1.31 to connect to a remote machine and call
scripts. For some reason, my code works on a windows machine (Windows
XP SP2), but it does not work on a HP Unix server (i think HP UX
11.11).

I use password authentication by putting it in a UserInfo class.

Dont mind the return object and how it is created. What matters is
that if i call this method twice, the second command hangs on HP Unix.
For example if i call

Entry entry = exec.execCommand(". /etc/profile;. ./.profile;ace_test ls -al /");
System.out.println(entry.getAttribute("output").getValues()[0].toString());
			
entry = exec.execCommand(". /etc/profile;. ./.profile;ace_test ls -l");			
System.out.println(entry.getAttribute("output").getValues()[0].toString());
			
entry = exec.execCommand(". /etc/profile;. ./.profile;ace_test ll");
System.out.println(entry.getAttribute("output").getValues()[0].toString());

entry = exec.execCommand(". /etc/profile;. ./.profile;ace_test ls ");
System.out.println(entry.getAttribute("output").getValues()[0].toString());

It will hang on the second execCommand and consume 100% CPU. Here is
the execCommand method:

public Entry execCommand(String command) throws Exception
    {
        logger.info("Starting execCommand");
        Entry returnObject = new Entry();
        BufferedReader bufRead = null;

        try{
            StringBuffer strBuff = new StringBuffer();
            if (!connected)
            {
                createSession();
            }
            Channel channel=session.openChannel("exec");
            ((ChannelExec)channel).setCommand(command);

            InputStream instream = channel.getInputStream() ;
     // I know, I could do this line and the line below in one, but
you *need* the inputstream for status input
            InputStreamReader input = new java.io.InputStreamReader (
instream ) ;
            bufRead = new java.io.BufferedReader ( input ) ;

            logger.info("executing command '" + command + "'");
            channel.connect();
            while ( true ) {
                while ( bufRead.ready () ) {                    //
line at a time, note the buffer can empty with more data available,
use the isEOF.. below to find out when it's truly donw
                    strBuff.append(bufRead.readLine()).append("\n");
                }
                if ( channel.isEOF() && instream.available() == 0 ) {
 // tells us when the command has completed returning data
                    break ;
                }
            }
            logger.info("Command executed.");

            returnObject.addAttributeValue("output", strBuff.toString());
            returnObject.addAttributeValue("exitstatus", "" +
channel.getExitStatus());

            channel.disconnect();

        }
        catch(Exception e){
            connected = false;
            logger.error("An unexpected error occured when executing
command '" + command + "': " + e.getClass().getName() + " " +
e.getMessage());
            throw e;
        }
        finally
        {
        	try{bufRead.close();}catch(Exception e){}
        }
        logger.info("Ending execCommand");
        return returnObject;
    }

Any help would be appreciated !!!

Guy