Hi Bros/Sis,
I use the jsch to execute interactive commands(that prompt for some
input/password) on the remote hosts which work perfectly fine.
There are some interactive commands which require a terminal for
execution eg. sudo/su.
For these commands I set the pty flag to true ie
"((ChannelExec)channel).setPty(true)"
This is also working perfectly fine, but for some instances the
execution hangs, the reason being the input/password is being piped even before
the pseudo terminal is launched
and hence the command is waiting infinitely for the password/input.
The following is the code snippet used .
======================================================================================================================================
//Set the pseudo terminal allocation flag to true
((ChannelExec)channel).setPty(true);
// Set the input stream with the input to be passed for the remote
command
byte[] cmdbuf = cmdInput.getBytes();
ByteArrayInputStream bi = new ByteArrayInputStream(cmdbuf);
channel.setInputStream(bi);
//Set the channel's error stream
ByteArrayOutputStream bo = new ByteArrayOutputStream();
((ChannelExec)channel).setErrStream(bo);
//Get the input stream of the channel
InputStream in=channel.getInputStream();
channel.connect();
byte[] tmp=new byte[1024];
while(true)
{
while(in.available()>0){
int i=in.read(tmp, 0, 1024);
if(i<0)break;
System.out.print(new String(tmp, 0, i));
//Hang is detected since the password is pumped in even before the
pseudo terminal is launched and now the command(sudo/su) is waiting infinitely
for the password.
}
if(channel.isClosed()){
System.out.println("exit-status: "+channel.getExitStatus());
break;
}
try{Thread.sleep(1000);}catch(Exception ee){}
}
channel.disconnect();
session.disconnect();
======================================================================================================================================
How do I go about resolving this issue.
i. Is there a way to introduce a delay or ensure that the pseudo terminal
and the command is launched and only then the input/password is piped in.
ii. If the above option is not feasible, is there a way to detect this hang
and once again set the input/password in the InputStream.
thanks,
Prakash
------------------------------------------------------------------------------
All the data continuously generated in your IT infrastructure
contains a definitive record of customers, application performance,
security threats, fraudulent activity, and more. Splunk takes this
data and makes sense of it. IT sense. And common sense.
http://p.sf.net/sfu/splunk-novd2d
_______________________________________________
JSch-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/jsch-users
