PRLinger
========
Structure used with the ``PR_SockOpt_Linger`` socket option to specify
the time interval (in :ref:`PRIntervalTime` units) to linger on closing a
socket if any data remain in the socket send buffer.
Syntax
~~~~~~
.. code::
#include <prio.h>
typedef struct PRLinger {
PRBool polarity;
PRIntervalTime linger;
} PRLinger;
Fields
~~~~~~
The structure has the following fields:
``polarity``
Polarity of the option's setting: ``PR_FALSE`` means the option is
off, in which case the value of ``linger`` is ignored. ``PR_TRUE``
means the option is on, and the value of ``linger`` will be used to
determine how long :ref:`PR_Close` waits before returning.
``linger``
Time (in :ref:`PRIntervalTime` units) to linger before closing if any
data remain in the socket send buffer.
Description
~~~~~~~~~~~
By default, :ref:`PR_Close` returns immediately, but if there are any data
remaining in the socket send buffer, the system attempts to deliver the
data to the peer. The ``PR_SockOpt_Linger`` socket option, with a value
represented by a structure of type :ref:`PRLinger`, makes it possible to
change this default as follows:
- If ``polarity`` is set to ``PR_FALSE``, :ref:`PR_Close` returns
immediately, but if there are any data remaining in the socket send
buffer, the runtime attempts to deliver the data to the peer.
- If ``polarity`` is set to ``PR_TRUE`` and ``linger`` is set to 0
(``PR_INTERVAL_NO_WAIT``), the runtime aborts the connection when it
is closed and discards any data remaining in the socket send buffer.
- If ``polarity`` is set to ``PR_TRUE`` and ``linger`` is nonzero, the
runtime *lingers* when the socket is closed. That is, if any data
remains in the socket send buffer, :ref:`PR_Close` blocks until either
all the data is sent and acknowledged by the peer or the interval
specified by ``linger`` expires.
