SSH Remote Shell

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

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MS Windows Visual C/C++ Libraries

Linux/CentOS C/C++ Libraries

MAC OS X C/C++ Libraries

Solaris C/C++ Libraries

C++ Builder Libraries

#include <C_CkSsh.h>

void ChilkatSample(void)
    {
    HCkSsh ssh;
    BOOL success;
    const char * hostname;
    long port;
    long channelNum;
    const char * termType;
    long widthInChars;
    long heightInChars;
    long pixWidth;
    long pixHeight;
    long n;
    long pollTimeoutMs;
    const char * cmdOutput;

    //  Important: It is helpful to send the contents of the
    //  ssh.LastErrorText property when requesting support.

    ssh = CkSsh_Create();

    //  Any string automatically begins a fully-functional 30-day trial.

    success = CkSsh_UnlockComponent(ssh,"30-day trial");
    if (success != TRUE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

    //  Connect to an SSH server:

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

    success = CkSsh_Connect(ssh,hostname,port);
    if (success != TRUE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

    //  Wait a max of 5 seconds when reading responses..
    CkSsh_putIdleTimeoutMs(ssh,5000);

    //  Authenticate using login/password:
    success = CkSsh_AuthenticatePw(ssh,"myLogin","myPassword");
    if (success != TRUE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

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

    channelNum = CkSsh_OpenSessionChannel(ssh);
    if (channelNum < 0) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

    //  Some SSH servers require a pseudo-terminal
    //  If so, include the call to SendReqPty.  If not, then
    //  comment out the call to SendReqPty.
    //  Note: The 2nd argument of SendReqPty is the terminal type,
    //  which should be something like "xterm", "vt100", "dumb", etc.
    //  A "dumb" terminal is one that cannot process escape sequences.
    //  Smart terminals, such as "xterm", "vt100", etc. process
    //  escape sequences.  If you select a type of smart terminal,
    //  your application will receive these escape sequences
    //  included in the command's output.  Use "dumb" if you do not
    //  want to receive escape sequences.  (Assuming your SSH
    //  server recognizes "dumb" as a standard dumb terminal.)

    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 = CkSsh_SendReqPty(ssh,channelNum,termType,widthInChars,heightInChars,pixWidth,pixHeight);
    if (success != TRUE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

    //  Start a shell on the channel:
    success = CkSsh_SendReqShell(ssh,channelNum);
    if (success != TRUE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

    //  Start a command in the remote shell.  This example
    //  will send a "ls -l" command to retrieve the directory listing.
    success = CkSsh_ChannelSendString(ssh,channelNum,"ls -l\n","ansi");
    if (success != TRUE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

    //  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 = CkSsh_ChannelSendEof(ssh,channelNum);
    if (success != TRUE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

    //  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 = CkSsh_ChannelReadAndPoll(ssh,channelNum,pollTimeoutMs);
    if (n < 0) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

    //  Close the channel:
    success = CkSsh_ChannelSendClose(ssh,channelNum);
    if (success != TRUE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

    //  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 = CkSsh_ChannelReceiveToClose(ssh,channelNum);
    if (success != TRUE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

    //  Let's pickup the accumulated output of the command:

    cmdOutput = CkSsh_getReceivedText(ssh,channelNum,"ansi");
    if (cmdOutput == 0 ) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        return;
    }

    //  Display the remote shell's command output:
    printf("%s\n",cmdOutput);

    //  Disconnect
    CkSsh_Disconnect(ssh);

    CkSsh_Dispose(ssh);

    }