Start a Remote Shell with QuickShell

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Demonstrates the Chilkat Ssh.QuickShell method, which starts a remote shell using the simplified sequence OpenSessionChannel → SendReqPty → SendReqShell. It takes no arguments and returns the shell channel number, or -1 on failure. The default PTY size is 80 columns by 24 rows.

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

BOOL success = NO;

//  Demonstrates the Ssh.QuickShell method, which starts a remote shell using the simplified
//  sequence OpenSessionChannel, SendReqPty, and SendReqShell.  It takes no arguments and returns
//  the shell channel number, or -1 on failure.  The default PTY size is 80 columns by 24 rows.

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

int sshPort = 22;
success = [ssh Connect: @"ssh.example.com" port: [NSNumber numberWithInt: sshPort]];
if (success == NO) {
    NSLog(@"%@",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.
NSString *password = @"mySshPassword";

success = [ssh AuthenticatePw: @"mySshLogin" password: password];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

//  Start the shell.  Note that QuickShell allocates a PTY, so the remote shell runs
//  interactively: it prints a command prompt and echoes the commands that are sent to it.
int channelNum = [[ssh QuickShell] intValue];
if (channelNum < 0) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

//  QuickShell returns as soon as the shell request is accepted -- it does not wait for or
//  consume the initial login text or prompt.
success = [ssh ChannelSendString: [NSNumber numberWithInt: channelNum] strData: @"uname -a; echo DONE_MARKER\n" charset: @"utf-8"];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

//  IMPORTANT: Set a read timeout before receiving until a match.  ReadTimeoutMs defaults to 0,
//  which means no limit -- without it, this call waits forever if the received data never
//  contains a match.
ssh.ReadTimeoutMs = [NSNumber numberWithInt:15000];

BOOL caseSensitive = NO;
success = [ssh ChannelReceiveUntilMatch: [NSNumber numberWithInt: channelNum] matchPattern: @"DONE_MARKER" charset: @"utf-8" caseSensitive: caseSensitive];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

NSString *output = [ssh GetReceivedText: [NSNumber numberWithInt: channelNum] charset: @"utf-8"];
if (ssh.LastMethodSuccess == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

NSLog(@"%@",output);

[ssh Disconnect];