Node.js

Check Whether an SSH Exit Status Was Received

Demonstrates the Chilkat Ssh.ChannelReceivedExitStatus method, which reports whether the server supplied an exit-status value for a channel. The only argument is the channel number. When it returns true, call GetChannelExitStatus to read the value.

Background: Always test this before reading the exit status, because the server is not required to send one for every channel type or command — treating a missing status as "0" would silently turn a failure into a success. Exit status is independent of EOF and CLOSE: it can arrive after EOF and either before or together with CLOSE.

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function chilkatExample() {

    var success = false;

    //  Demonstrates the Ssh.ChannelReceivedExitStatus method, which reports whether the server
    //  supplied an exit-status value for a channel.  The only argument is the channel number.  When
    //  it returns true, call GetChannelExitStatus to read the value.

    var ssh = new chilkat.Ssh();

    var sshPort = 22;
    success = ssh.Connect("ssh.example.com",sshPort);
    if (success == false) {
        console.log(ssh.LastErrorText);
        return;
    }

    //  Normally you would not hard-code the password in source.  You should instead obtain it
    //  from an interactive prompt, environment variable, or a secrets vault.
    var password = "mySshPassword";

    success = ssh.AuthenticatePw("mySshLogin",password);
    if (success == false) {
        console.log(ssh.LastErrorText);
        return;
    }

    var channelNum = ssh.OpenSessionChannel();
    if (channelNum < 0) {
        console.log(ssh.LastErrorText);
        return;
    }

    success = ssh.SendReqExec(channelNum,"test -f /etc/hosts");
    if (success == false) {
        console.log(ssh.LastErrorText);
        return;
    }

    //  IMPORTANT: Set a read timeout.  ReadTimeoutMs defaults to 0, which means no limit -- without
    //  it, this call waits forever if the server never sends channel close.
    ssh.ReadTimeoutMs = 15000;

    success = ssh.ChannelReceiveToClose(channelNum);
    if (success == false) {
        console.log(ssh.LastErrorText);
        return;
    }

    //  The server is not required to send an exit status for every channel type or command.
    if (ssh.ChannelReceivedExitStatus(channelNum)) {
        var exitStatus = ssh.GetChannelExitStatus(channelNum);
        console.log("Exit status: " + exitStatus);
    }
    else {
        console.log("The server did not provide an exit status.");
    }

    ssh.Disconnect();

}

chilkatExample();