Re: Unable to execute program

[Aris Adamantiadis <aris@xxxxxxxxxxxx>]

Hi,

Have a look at the output of stderr : ssh_channel_read(..., 1);

This will give more info about what's happening.
Also, ssh_channel_request_exec is returning immediatly, and does not
return the exit code of the process. For this, you should look at
ssh_channel_exit_status.

Kr,

Aris

Le 14/10/11 12:32, h2c357 h2c357 a écrit :
> Hi all,
> 
> I am running sshd on Fedora Core 15 and my ssh client is running on
> Window XP(sorry). I have an executable which requires some .so files to
> run. The whole directory structure becomes something like following:
> 
> /home/h2c357/app/bin/my_executable (This is the path my executable)
> 
> (my lib directories are stored in following locations)
> /home/h2c357/app/lib/
> /usr/lib/oracle/11.2/client64/lib
> 
> Now when I try to execute my_executable on remote machine via libssh
> client, I do not get any error (channel_request_exec() returns 0) but
> when I try to read program output (it prints some data it reads from the
> db), I get bytes read count 0. Also system monitor on FC15 does not show
> my process.
> 
> Please let me know what I might be doing wrong.
> 
> Below is the code that I have written:
> 
>             ssh_channel createChannel(ssh_session session_)
>             {
>                 ssh_channel channel;
>                 bool isChannelCreated_ = true;
> 
>                 channel = channel_new(session_);
>                 if (channel == NULL)
>                 {
>                     isChannelCreated_ = false;
>                     return NULL;
>                 }
> 
>                 if (channel_open_session(channel) != SSH_OK)
>                 {
>                     isChannelCreated_ = false;
>                     channel_free(channel);
>                     return NULL;
>                 }
>                
>                 return channel;
>             }
> 
>             void execute(std::string appCmdLine, std::string ldCommand)
>             {
>                     int execStatus_ = 0;
>                     ssh_channel channel = createChannel();
>                     if (!isChannelCreated_ || channel == NULL)
>                     {
>                         execStatus_ = EXEC_STATUS_FAILURE;
>                         return;
>                     }
> 
>                     int rc = channel_request_exec(channel,
> appCmdLine.c_str());
>                     if (rc != SSH_OK)
>                     {
>                         execStatus_ = EXEC_STATUS_FAILURE;
>                         channel_close(channel);
>                         channel_free(channel);
>                     }
>                     else
>                     {
>                         execStatus_ = EXEC_STATUS_SUCCESS;
> 
>                         char buffer[256];
>                         unsigned int nbytes;
> 
>                         nbytes = channel_read(channel, buffer,
> sizeof(buffer), 0);
>                         while (nbytes > 0)
>                         {
>                             if (fwrite(buffer, 1, nbytes, stdout) != nbytes)
>                             {
>                                 ssh_channel_close(channel);
>                                 ssh_channel_free(channel);
>                                 return;
>                             }
>                             nbytes = ssh_channel_read(channel, buffer,
> sizeof(buffer), 0);
>                         }
> 
>                         if (nbytes < 0)
>                         {
>                             ssh_channel_close(channel);
>                             ssh_channel_free(channel);
>                             return;
>                         }
>                         channel_send_eof(channel);
>                         closeChannel(channel);
>                     }
>                 }
>