Rust

Get Received SSH Text into a StringBuilder

Demonstrates the Chilkat Ssh.GetReceivedSb method, which decodes a channel's receive buffer and appends the text to a StringBuilder. The arguments are the channel number, the charset, and the StringBuilder. The receive buffer is cleared afterward.

Background: Because this appends rather than replaces, it is the natural choice for accumulating output across repeated reads — call it in a loop and the StringBuilder grows into the complete transcript. It also avoids creating a new string on every retrieval, which matters when a command produces a large amount of text.

Chilkat Rust Downloads

Download Chilkat for Rust

Rust


// Demonstrates the Ssh.GetReceivedSb method, which decodes the channel's receive buffer and
// appends the text to a StringBuilder.  The 1st argument is the channel number, the 2nd is the
// charset, and the 3rd is the StringBuilder.  The receive buffer is cleared afterward.

let ssh = chilkat::Ssh::new();

let ssh_port = 22;
if ssh.connect("ssh.example.com", ssh_port).is_err() {
    println!("{}", ssh.last_error_text());
    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.
let password = "mySshPassword".to_string();

if ssh.authenticate_pw("mySshLogin", &password).is_err() {
    println!("{}", ssh.last_error_text());
    return;
}

let channel_num = ssh.open_session_channel();
if channel_num < 0 {
    println!("{}", ssh.last_error_text());
    return;
}

if ssh.send_req_exec(channel_num, "ls -l /tmp").is_err() {
    println!("{}", ssh.last_error_text());
    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.set_read_timeout_ms(15000);

if ssh.channel_receive_to_close(channel_num).is_err() {
    println!("{}", ssh.last_error_text());
    return;
}

// Append the received text to a StringBuilder.  Existing content is preserved.
let sb = chilkat::StringBuilder::new();
if ssh.get_received_sb(channel_num, "utf-8", &sb).is_err() {
    println!("{}", ssh.last_error_text());
    return;
}

println!("Characters received: {}", sb.length());
let output = sb.get_as_string().unwrap_or_default();
println!("{}", output);

ssh.disconnect();