-spec adjust_window(ConnectionRef, ChannelId, NumOfBytes) -> ok
                 when
                     ConnectionRef :: ssh:connection_ref(),
                     ChannelId :: ssh:channel_id(),
                     NumOfBytes :: integer().

Adjusts the SSH flow control window. This is to be done by both the client- and server-side channel processes.

Note

Channels implemented with the ssh_client_channel behavior do not normally need to call this function as flow control is handled by the behavior. The behavior adjusts the window every time the callback handle_ssh_msg/2 returns after processing channel data.

-spec close(ConnectionRef, ChannelId) -> ok
         when ConnectionRef :: ssh:connection_ref(), ChannelId :: ssh:channel_id().

A server- or client-channel process can choose to close their session by sending a close event.

Note

This function is called by the ssh_client_channel behavior when the channel is terminated, see ssh_client_channel. Thus, channels implemented with the behavior are not to call this function explicitly.

-spec exec(ConnectionRef, ChannelId, Command, Timeout) -> result()
        when
            ConnectionRef :: ssh:connection_ref(),
            ChannelId :: ssh:channel_id(),
            Command :: string(),
            Timeout :: timeout().

Is to be called by a client-channel process to request that the server starts executing the given command. The result is several messages according to the following pattern. The last message is a channel close message, as the exec request is a one-time execution that closes the channel when it is done.

• N x data message(s) - The result of executing the command can be only one line or thousands of lines depending on the command.

• 0 or 1 x eof message - Indicates that no more data is to be sent.

• 0 or 1 x exit signal message - Not all systems send signals. For details on valid string values, see RFC 4254, Section 6.10

• 0 or 1 x exit status message - It is recommended by the SSH Connection Protocol to send this message, but that is not always the case.

• 1 x closed status message - Indicates that the ssh_client_channel started for the execution of the command has now been shut down.

See the User's Guide section on One-Time Execution for examples.

-spec exit_status(ConnectionRef, ChannelId, Status) -> ok
               when
                   ConnectionRef :: ssh:connection_ref(),
                   ChannelId :: ssh:channel_id(),
                   Status :: integer().

Is to be called by a server-channel process to send the exit status of a command to the client.

-spec ptty_alloc(ConnectionRef, ChannelId, Options) -> result()
              when
                  ConnectionRef :: ssh:connection_ref(),
                  ChannelId :: ssh:channel_id(),
                  Options :: proplists:proplist().

Equivalent to ptty_alloc/4.

-spec ptty_alloc(ConnectionRef, ChannelId, Options, Timeout) -> result()
              when
                  ConnectionRef :: ssh:connection_ref(),
                  ChannelId :: ssh:channel_id(),
                  Options :: proplists:proplist(),
                  Timeout :: timeout().

Sends an SSH Connection Protocol pty_req, to allocate a pseudo-terminal. Is to be called by an SSH client process.

Options:

• {term, string()} - Defaults to os:getenv("TERM") or vt100 if it is undefined.

• {width, integer()} - Defaults to 80 if pixel_width is not defined.

• {height, integer()} - Defaults to 24 if pixel_height is not defined.

• {pixel_width, integer()} - Is disregarded if width is defined.

• {pixel_height, integer()} - Is disregarded if height is defined.

• {pty_opts, [{posix_atom(), integer()}]} - Option can be an empty list. Otherwise, see possible POSIX names in Section 8 in RFC 4254.

-spec reply_request(ConnectionRef, WantReply, Status, ChannelId) -> ok
                 when
                     ConnectionRef :: ssh:connection_ref(),
                     WantReply :: boolean(),
                     Status :: req_status(),
                     ChannelId :: ssh:channel_id().

Sends status replies to requests where the requester has stated that it wants a status report, that is, WantReply = true. If WantReply is false, calling this function becomes a "noop". Is to be called while handling an SSH Connection Protocol message containing a WantReply boolean value.

-spec send(connection_ref(), channel_id(), iodata()) -> ok | {error, timeout | closed}.

Equivalent to send/5.

-spec send(connection_ref(), channel_id(), iodata(), timeout()) -> ok | {error, reason()};
    (connection_ref(), channel_id(), ssh_data_type_code(), iodata()) -> ok | {error, reason()}.

Equivalent to send/5.

-spec send(connection_ref(), channel_id(), ssh_data_type_code(), iodata(), timeout()) ->
        ok | {error, reason()}.

send(ConnectionRef, ChannelId, Type, Data, TimeOut) -> ok | Error

Is to be called by client- and server-channel processes to send data to each other.

The function subsystem/4 and subsequent calls of send/3,4,5 must be executed in the same process.

-spec send_eof(ConnectionRef, ChannelId) -> ok | {error, closed}
            when ConnectionRef :: ssh:connection_ref(), ChannelId :: ssh:channel_id().

Sends EOF on channel ChannelId.

-spec session_channel(ConnectionRef, Timeout) -> Result
                   when
                       ConnectionRef :: ssh:connection_ref(),
                       Timeout :: timeout(),
                       Result :: {ok, ssh:channel_id()} | {error, reason()}.

Equivalent to session_channel/4.

-spec session_channel(ConnectionRef, InitialWindowSize, MaxPacketSize, Timeout) -> Result
                   when
                       ConnectionRef :: ssh:connection_ref(),
                       InitialWindowSize :: pos_integer() | undefined,
                       MaxPacketSize :: pos_integer() | undefined,
                       Timeout :: timeout(),
                       Result :: {ok, ssh:channel_id()} | {error, reason()}.

Opens a channel for an SSH session. The channel id returned from this function is the id used as input to the other functions in this module.

-spec setenv(ConnectionRef, ChannelId, Var, Value, Timeout) -> success
          when
              ConnectionRef :: ssh:connection_ref(),
              ChannelId :: ssh:channel_id(),
              Var :: string(),
              Value :: string(),
              Timeout :: timeout().

Environment variables can be passed before starting the shell/command. Is to be called by a client channel processes.

-spec shell(ConnectionRef, ChannelId) -> Result
         when
             ConnectionRef :: ssh:connection_ref(),
             ChannelId :: ssh:channel_id(),
             Result :: ok | success | failure | {error, timeout}.

Is to be called by a client channel process to request that the user default shell (typically defined in /etc/passwd in Unix systems) is executed at the server end.

Note: the return value is ok instead of success unlike in other functions in this module. This is a fault that was introduced so long ago that any change would break a large number of existing software.

-spec subsystem(ConnectionRef, ChannelId, Subsystem, Timeout) -> result()
             when
                 ConnectionRef :: ssh:connection_ref(),
                 ChannelId :: ssh:channel_id(),
                 Subsystem :: string(),
                 Timeout :: timeout().

Is to be called by a client-channel process for requesting to execute a predefined subsystem on the server.

The function subsystem/4 and subsequent calls of send/3,4,5 must be executed in the same process.