Objective-C

SSH Remote Shell Multiple Commands

See more SSH Examples

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. Objective-C

#import <CkoSsh.h>
#import <NSString.h>

BOOL success = NO;

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

CkoSsh *ssh = [[CkoSsh alloc] init];

// This is the prompt we'll be expecting to find in
// the output of the remote shell.
NSString *myPrompt = 0;
myPrompt = @"chilkat@ubuntu:~/workspace$";

NSString *cmdOutput = 0;

// Connect to an SSH server:
NSString *hostname = 0;
int port;

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

success = [ssh Connect: hostname port: [NSNumber numberWithInt: port]];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

// Wait a max of 10 seconds when reading responses..
ssh.IdleTimeoutMs = [NSNumber numberWithInt:10000];

// Authenticate using login/password:
success = [ssh AuthenticatePw: @"myLogin" password: @"myPassword"];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

// Open a session channel.  (It is possible to have multiple
// session channels open simultaneously.)
int channelNum;
channelNum = [[ssh OpenSessionChannel] intValue];
if (channelNum < 0) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

NSString *termType = @"dumb";
int widthInChars = 120;
int heightInChars = 40;
// Use 0 for pixWidth and pixHeight when the dimensions
// are set in number-of-chars.
int pixWidth = 0;
int pixHeight = 0;
success = [ssh SendReqPty: [NSNumber numberWithInt: channelNum] xTermEnvVar: termType widthInChars: [NSNumber numberWithInt: widthInChars] heightInRows: [NSNumber numberWithInt: heightInChars] pixWidth: [NSNumber numberWithInt: pixWidth] pixHeight: [NSNumber numberWithInt: pixHeight]];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

// Start a shell on the channel:
success = [ssh SendReqShell: [NSNumber numberWithInt: channelNum]];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

//  Run the 1st command in the remote shell, which will be to
//  "cd" to a subdirectory.
success = [ssh ChannelSendString: [NSNumber numberWithInt: channelNum] strData: @"cd workspace\r\n" charset: @"ansi"];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

// Retrieve the output.
success = [ssh ChannelReceiveUntilMatch: [NSNumber numberWithInt: channelNum] matchPattern: myPrompt charset: @"ansi" caseSensitive: YES];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

//  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: [NSNumber numberWithInt: channelNum] charset: @"ansi"];
if (ssh.LastMethodSuccess != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

NSLog(@"%@",cmdOutput);

//  Run the 2nd command in the remote shell, which will be
//  to "ls" the directory.
success = [ssh ChannelSendString: [NSNumber numberWithInt: channelNum] strData: @"ls\r\n" charset: @"ansi"];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

// Retrieve and display the output.
success = [ssh ChannelReceiveUntilMatch: [NSNumber numberWithInt: channelNum] matchPattern: myPrompt charset: @"ansi" caseSensitive: YES];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

cmdOutput = [ssh GetReceivedText: [NSNumber numberWithInt: channelNum] charset: @"ansi"];
if (ssh.LastMethodSuccess != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

NSLog(@"%@",cmdOutput);

//  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: [NSNumber numberWithInt: channelNum] strData: @"ls -l\r\n" charset: @"ansi"];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    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 = [ssh ChannelSendEof: [NSNumber numberWithInt: channelNum]];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    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.
int n;
int pollTimeoutMs = 2000;
n = [[ssh ChannelReadAndPoll: [NSNumber numberWithInt: channelNum] pollTimeoutMs: [NSNumber numberWithInt: pollTimeoutMs]] intValue];
if (n < 0) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

// Close the channel:
success = [ssh ChannelSendClose: [NSNumber numberWithInt: channelNum]];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    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 = [ssh ChannelReceiveToClose: [NSNumber numberWithInt: channelNum]];
if (success != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

cmdOutput = [ssh GetReceivedText: [NSNumber numberWithInt: channelNum] charset: @"ansi"];
if (ssh.LastMethodSuccess != YES) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

NSLog(@"%@",cmdOutput);

// Disconnect
[ssh Disconnect];