Index for Section 7

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tirdwr(7)
NAME
  tirdwr - STREAMS module for reads and writes by TI transport users

DESCRIPTION
  The tirdwr module is a STREAMS module that provides a transport user
  supporting the Transport Interface (TI) with an alternate interface to a
  transport protocol provider supporting TI. This alternate interface allows
  the transport user to communicate with the transport protocol provider
  using the read() and write() functions. It can also continue to use the
  putmsg(), putpmsg() and getmsg(), getpmsg() functions, but these functions
  will only transfer data messages between the user process and device
  stream.

  The user places the tirdwr module on a device stream by calling the STREAMS
  I_PUSH ioctl() function. Once the module has been pushed on the device
  stream, the user cannot make further calls to TI functions. If the user
  attempts to do this, an error occurs on the stream. After the error is
  detected, subsequent calls fail with errno set to [EPROTO]. The user
  removes the tirdwr module from a device stream by calling the STREAMS I_POP
  ioctl() function.

  Module Behavior When Pushed and Popped

  When the tirdwr module is pushed on a device stream, it checks any existing
  messages that are destined for the user to determine their message type. If
  existing messages are regular data messages, it forwards the messages to
  the user. It ignores any messages related to process management, such as
  messages that generate signals to the user. If any other messages are
  present, it returns an error to the user request with errno set to
  [EPROTO].

  When the tirdwr module is popped from a device stream, it checks whether an
  orderly release indication has been previously received from the transport
  protocol provider. If an orderly release indication was received, it sends
  an orderly release request to the remote side of the transport connection.
  The tirdwr module also acts this way when the device stream is closed.

  Module Behavior for Reads and Writes

  When the tirdwr module receives messages from the transport protocol
  provider that do not contain a control part (see the putmsg(), putpmsg()
  and getmsg(), getpmsg() reference pages), it transparently passes the
  messages to its upstream neighbor. The exception is for zero-length data
  messages, where the module frees the message and does not pass them to its
  upstream neighbor.

  When the module receives messages from the transport protocol provider that
  contain a control part, it takes one of the following actions:

    ·  For data messages with a control part, it removes this part, then
       passes the message to its upstream neighbor.

    ·  For messages that represent expedited data, it generates an error.
       Further system calls will fail with errno set to [EPROTO].

    ·  For messages that represent expedited data, it generates an error.
       Further system calls will fail with errno set to [EPROTO].

    ·  For messages that represent an orderly release indication from the
       transport protocol provider, it generates a zero-length data message,
       indicating the End-of-File (EOF), and sends this message upstream to
       the reading process. The original message containing the orderly
       release indication is freed.

    ·  For messages that represent an abortive disconnect indication from the
       transport protocol provider, it causes all further write() and
       putmsg(), putpmsg() calls to fail with errno set to [ENXIO].
       Subsequent read() and getmsg(), getpmsg() calls will return zero-
       length data messages indicating the End-of-File (EOF), once all
       previous data has been read.

    ·  For all other messages, it generates an error, and further calls will
       fail with errno set to [EPROTO].

SEE ALSO
  Functions: intro(2), getmsg(2), getpmsg(2), putmsg(2), putpmsg(2), read(2),
  write(2)

  Interfaces: streamio(7)

Index for Section 7

Alphabetical listing for T

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