(Perl) SSH Remote Shell Multiple Commands

Demonstrates how to start a shell on a remote SSH server, run a command, and retrieve the output, then run the next command, retrieve the output, etc.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

# This example assumes the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

$ssh = chilkat::CkSsh->new();

# This is the prompt we'll be expecting to find in
# the output of the remote shell.

$myPrompt = 'chilkat@ubuntu:~/workspace$';

# Connect to an SSH server:

# Hostname may be an IP address or hostname:
$hostname = "www.some-ssh-server.com";
$port = 22;

$success = $ssh->Connect($hostname,$port);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

# Wait a max of 10 seconds when reading responses..
$ssh->put_IdleTimeoutMs(10000);

# Authenticate using login/password:
$success = $ssh->AuthenticatePw("myLogin","myPassword");
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

# Open a session channel.  (It is possible to have multiple
# session channels open simultaneously.)

$channelNum = $ssh->OpenSessionChannel();
if ($channelNum < 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

$termType = "dumb";
$widthInChars = 120;
$heightInChars = 40;
# Use 0 for pixWidth and pixHeight when the dimensions
# are set in number-of-chars.
$pixWidth = 0;
$pixHeight = 0;
$success = $ssh->SendReqPty($channelNum,$termType,$widthInChars,$heightInChars,$pixWidth,$pixHeight);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

# Start a shell on the channel:
$success = $ssh->SendReqShell($channelNum);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

#  Run the 1st command in the remote shell, which will be to
#  "cd" to a subdirectory.
$success = $ssh->ChannelSendString($channelNum,"cd workspace\r\n","ansi");
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

# Retrieve the output.
$success = $ssh->ChannelReceiveUntilMatch($channelNum,$myPrompt,"ansi",1);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

#  Display what we've received so far.  This clears
#  the internal receive buffer, which is important.
#  After we send the command, we'll be reading until
#  the next command prompt.  If the command prompt
#  is already in the internal receive buffer, it'll think it's
#  already finished...
$cmdOutput = $ssh->getReceivedText($channelNum,"ansi");
if ($ssh->get_LastMethodSuccess() != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

print $cmdOutput . "\r\n";

#  Run the 2nd command in the remote shell, which will be
#  to "ls" the directory.
$success = $ssh->ChannelSendString($channelNum,"ls\r\n","ansi");
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

# Retrieve and display the output.
$success = $ssh->ChannelReceiveUntilMatch($channelNum,$myPrompt,"ansi",1);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

$cmdOutput = $ssh->getReceivedText($channelNum,"ansi");
if ($ssh->get_LastMethodSuccess() != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

print $cmdOutput . "\r\n";

#  Start the final command in the remote shell.  This example
#  will send a "ls -l" command to retrieve the long format directory listing.
$success = $ssh->ChannelSendString($channelNum,"ls -l\r\n","ansi");
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

# Send an EOF.  This tells the server that no more data will 
# be sent on this channel.  The channel remains open, and
# the SSH client may still receive output on this channel.
$success = $ssh->ChannelSendEof($channelNum);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

# Read whatever output may already be available on the
# SSH connection.  ChannelReadAndPoll returns the number of bytes
# that are available in the channel's internal buffer that
# are ready to be "picked up" by calling GetReceivedText
# or GetReceivedData.
# A return value of -1 indicates failure.
# A return value of -2 indicates a failure via timeout.

# The ChannelReadAndPoll method waits
# for data to arrive on the connection usingi the IdleTimeoutMs
# property setting.  Once the first data arrives, it continues
# reading but instead uses the pollTimeoutMs passed in the 2nd argument:
# A return value of -2 indicates a timeout where no data is received.

$pollTimeoutMs = 2000;
$n = $ssh->ChannelReadAndPoll($channelNum,$pollTimeoutMs);
if ($n < 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

# Close the channel:
$success = $ssh->ChannelSendClose($channelNum);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

# Perhaps we did not receive all of the commands output.
# To make sure,  call ChannelReceiveToClose to accumulate any remaining
# output until the server's corresponding "channel close" is received.
$success = $ssh->ChannelReceiveToClose($channelNum);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

$cmdOutput = $ssh->getReceivedText($channelNum,"ansi");
if ($ssh->get_LastMethodSuccess() != 1) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

print $cmdOutput . "\r\n";

# Disconnect
$ssh->Disconnect();