ssh_client_channel

call(ChannelRef, Msg) ->

OTP 21.0

call(ChannelRef, Msg, Timeout) -> Reply | {error, Reason}

OTP 21.0

Types

As returned by start_link/4

Makes a synchronous call to the channel process by sending a message and waiting until a reply arrives, or a time-out occurs. The channel calls Module:handle_call/3 to handle the message. If the channel process does not exist, {error, closed} is returned.

cast(ChannelRef, Msg) -> ok

OTP 21.0

Types

As returned by start_link/4

Sends an asynchronous message to the channel process and returns ok immediately, ignoring if the destination node or channel process does not exist. The channel calls Module:handle_cast/2 to handle the message.

enter_loop(State) -> _

OTP 21.0

Types

as returned by init/1

Makes an existing process an ssh_client_channel (replaces ssh_channel) process. Does not return, instead the calling process enters the ssh_client_channel (replaces ssh_channel) process receive loop and become an ssh_client_channel process. The process must have been started using one of the start functions in proc_lib, see the proc_lib(3) manual page in STDLIB. The user is responsible for any initialization of the process and must call init/1.

init(Options) -> {ok, State} | {ok, State, Timeout} | {stop, Reason}

OTP 21.0

Types

The following options must be present:

{channel_cb, atom()}

The module that implements the channel behaviour.

{init_args(), list()}

The list of arguments to the init function of the callback module.

{cm,ssh:connection_ref()}

Reference to the ssh connection as returned by ssh:connect/3.

{channel_id,ssh:channel_id()}

Id of the ssh channel as returned by ssh_connection:session_channel/2,4.

reply(Client, Reply) -> _

OTP 21.0

Types

This function can be used by a channel to send a reply to a client that called call/[2,3] when the reply cannot be defined in the return value of Module:handle_call/3.

Client must be the From argument provided to the callback function handle_call/3. Reply is an arbitrary term, which is given back to the client as the return value of call/[2,3].

start(SshConnection, ChannelId, ChannelCb, CbInitArgs) ->

OTP 21.0

start_link(SshConnection, ChannelId, ChannelCb, CbInitArgs) -> {ok, ChannelRef} | {error, Reason}

OTP 21.0

Types

As returned by ssh:connect/3 As returned by ssh_connection:session_channel/[2,4].

Name of the module implementing the service-specific parts of the channel.

Argument list for the init function in the callback module.

Starts a process that handles an SSH channel. It is called internally, by the ssh daemon, or explicitly by the ssh client implementations. The behavior sets the trap_exit flag to true.

Module:code_change(OldVsn, State, Extra) -> {ok, NewState}

OTP 21.0

Types

In the case of an upgrade, OldVsn is Vsn, and in the case of a downgrade, OldVsn is {down,Vsn}. Vsn is defined by the vsn attribute(s) of the old version of the callback module Module. If no such attribute is defined, the version is the checksum of the BEAM file.

Internal state of the channel.

Passed "as-is" from the {advanced,Extra} part of the update instruction.

Converts process state when code is changed.

This function is called by a client-side channel when it is to update its internal state during a release upgrade or downgrade, that is, when the instruction {update,Module,Change,...}, where Change={advanced,Extra}, is given in the appup file. For more information, refer to Section 9.11.6 Release Handling Instructions in the System Documentation.

Module:init(Args) -> {ok, State} | {ok, State, timeout()} | {stop, Reason}

OTP 21.0

Types

Last argument to start_link/4.

Makes necessary initializations and returns the initial channel state if the initializations succeed.

For more detailed information on time-outs, see Section Callback timeouts.

Module:handle_call(Msg, From, State) -> Result

OTP 21.0

Types

Is to be used as argument to reply/2 Will be the return value of call/[2,3]

Handles messages sent by calling call/[2,3]

For more detailed information on time-outs,, see Section Callback timeouts.

Module:handle_cast(Msg, State) -> Result

OTP 21.0

Types

Handles messages sent by calling cast/2.

For more detailed information on time-outs, see Section Callback timeouts.

Module:handle_msg(Msg, State) -> {ok, State} | {stop, ChannelId, State}

OTP 21.0

Types

Handles other messages than SSH Connection Protocol, call, or cast messages sent to the channel.

Possible Erlang 'EXIT' messages is to be handled by this function and all channels are to handle the following message.

{ssh_channel_up,ssh:channel_id(),ssh:connection_ref()}

This is the first message that the channel receives. It is sent just before the init/1 function returns successfully. This is especially useful if the server wants to send a message to the client without first receiving a message from it. If the message is not useful for your particular scenario, ignore it by immediately returning {ok, State}.

Module:handle_ssh_msg(Msg, State) -> {ok, State} | {stop, ChannelId, State}

OTP 21.0

Types

Handles SSH Connection Protocol messages that may need service-specific attention. For details, see ssh_connection:event().

The following message is taken care of by the ssh_client_channel behavior.

{closed,ssh:channel_id()}

The channel behavior sends a close message to the other side, if such a message has not already been sent. Then it terminates the channel with reason normal.

Module:terminate(Reason, State) -> _

OTP 21.0

Types

This function is called by a channel process when it is about to terminate. Before this function is called, ssh_connection:close/2 is called, if it has not been called earlier. This function does any necessary cleaning up. When it returns, the channel process terminates with reason Reason. The return value is ignored.