Manual Pages for UNIX Operating System command usage for man port_alert

Standard C Library Functions                       port_alert(3C)



NAME
     port_alert - set a port in alert mode

SYNOPSIS
     #include 

     int port_alert(int port, int flags, int events, void *user);


DESCRIPTION
     The port_alert() function transitions a port into or out  of
     alert  mode.   A  port in alert mode immediately awakens all
     threads blocked  in  port_get(3C)  or  port_getn(3C).  These
     threads return with an alert notification that consists of a
     single    port_event_t    structure    with    the    source
     PORT_SOURCE_ALERT.  Subsequent  threads  trying  to retrieve
     events from a port that is in alert mode will return immedi-
     ately with the alert notification.


     A port is  transitioned  into  alert  mode  by  calling  the
     port_alert() function with a non-zero events parameter.  The
     specified events and user parameters will be made  available
     in  the  portev_events  and  the  portev_user members of the
     alert notification, respectively. The flags argument  deter-
     mines the mode of operation of the alert mode:

         o    If flags is  set  to  PORT_ALERT_SET,  port_alert()
              sets  the  port  in  alert  mode independent of the
              current state of the port.  The  portev_events  and
              portev_user members are set or updated accordingly.

         o    If flags is set to PORT_ALERT_UPDATE and  the  port
              is  not in alert mode, port_alert() transitions the
              port  into  alert  mode.   The  portev_events   and
              portev_user members are set accordingly.

         o    If flags is set to PORT_ALERT_UPDATE and  the  port
              is already in alert mode, port_alert() returns with
              an error value of EBUSY.


     PORT_ALERT_SET and PORT_ALERT_UPDATE are mutually exclusive.


     A port is transitioned out of  alert  mode  by  calling  the
     port_alert() function with a zero events parameter.


     Events can be queued to a port that is in  alert  mode,  but
     they  will not be retrievable until the port is transitioned
     out of alert mode.



SunOS 5.11           Last change: 1 Oct 2003                    1






Standard C Library Functions                       port_alert(3C)



RETURN VALUES
     Upon succesful completion, 0 is returned. Otherwise,  -1  is
     returned and errno is set to indicate the error.

ERRORS
     The port_alert() function will fail if:

     EBADF     The port identifier is not valid.


     EBADFD    The port  argument  is  not  an  event  port  file
               descriptor.


     EBUSY     The port is already in alert mode.


     EINVAL    Mutually exclusive flags are set.


ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:



     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Architecture                | all                         |
    |_____________________________|_____________________________|
    | Availability                | SUNWcs, system/header       |
    |_____________________________|_____________________________|
    | Interface Stability         | Committed                   |
    |_____________________________|_____________________________|
    | MT-Level                    | Safe                        |
    |_____________________________|_____________________________|


SEE ALSO
     port_associate(3C),      port_create(3C),      port_get(3C),
     port_send(3C), attributes(5)













SunOS 5.11           Last change: 1 Oct 2003                    2