Open a Custom SSH Channel Type

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Demonstrates the Chilkat Ssh.OpenCustomChannel method, which requests a channel whose application-defined type is supplied as the only argument. It returns the channel number, or -1 if the server rejects the channel. The server must implement that channel type.

Background: The SSH protocol allows vendor- and application-specific channel types beyond the standard session and direct-tcpip kinds; by convention these carry an @domain suffix to avoid name collisions. This method is the escape hatch for talking to a server that implements such a type. On rejection, inspect ChannelOpenFailCode to learn why.

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#include <C_CkSsh.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSsh ssh;
    int sshPort;
    const char *password;
    const char *channelType;
    int channelNum;

    success = FALSE;

    //  Demonstrates the Ssh.OpenCustomChannel method, which requests a custom SSH channel whose
    //  application-defined type is supplied as the only argument.  It returns the channel number,
    //  or -1 if the server rejects the channel.  The server must implement that channel type.

    ssh = CkSsh_Create();

    sshPort = 22;
    success = CkSsh_Connect(ssh,"ssh.example.com",sshPort);
    if (success == FALSE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        CkSsh_Dispose(ssh);
        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.
    password = "mySshPassword";

    success = CkSsh_AuthenticatePw(ssh,"mySshLogin",password);
    if (success == FALSE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        CkSsh_Dispose(ssh);
        return;
    }

    //  Request an application-defined channel type.  The server must support it.
    channelType = "my-custom-channel@example.com";
    channelNum = CkSsh_OpenCustomChannel(ssh,channelType);
    if (channelNum < 0) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        CkSsh_Dispose(ssh);
        return;
    }

    printf("Opened custom channel: %d\n",channelNum);

    //  The channel is used with the normal channel send, receive, EOF, CLOSE, and release methods.

    CkSsh_Disconnect(ssh);


    CkSsh_Dispose(ssh);

    }