EvmConnCheck(3)EvmConnCheck(3)NAMEEvmConnCheck(), EvmConnWait(), EvmConnDispatch(), EvmConnFlush()-
maintain connection with the EVM daemon
SYNOPSIS
Library
EVM Support Library
Parameters
connection The EVM connection that is to be monitored. See the Evm‐
ConnCreate(3) manpage.
IOWaiting This is the return operand. Possible values for this oper‐
and are the following:
There is no outstanding I/O activity on the connection.
There is outstanding I/O activity on the connection.
The client needs to call to handle the out‐
standing activity.
timeout If the timeout value is NULL, it specifies that is to wait
until there is activity on the connection. If the timeout
value is not NULL, it specifies the amount of time that waits
for activity on the connection.
count Receives a count of messages queued for sending to the EVM
daemon.
DESCRIPTION
The routine checks whether there is any I/O activity outstanding on the
connection. If there is activity, IOWaiting is set to The program is
to then call to handle it. If there is no outstanding I/O activity,
IOWaiting is set to An response from this function does not guarantee
that an event has arrived. An response simply means that there is a
message on the connection that needs to be handled.
The routine blocks until activity is detected on the connection. If
timeout is not NULL, it specifies the amount of time that the function
waits for activity on the connection before returning with a status of
The routine handles one incoming I/O message on the connection, calling
the client's callback function as needed. If there is no message
awaiting processing, the function returns immediately. Calling this
function is not guaranteed to invoke the connection's callback func‐
tion. If the callback is invoked, it is not necessarily true that an
event has arrived.
The routine attempts to send to the EVM daemon any messages that are
queued for output as a result of earlier calls on a connection that is
marked as a non-blocking connection. The routine continues to send
messages from the queue, until either all messages have been sent or
until the send buffer is full. On return, if the count output parame‐
ter is a number greater than zero, then that number is the number of
messages still queued for sending. returns See EvmConnControl(3) for
more information.
RETURN VALUE
The operation completed without error.
One of the arguments to the function is invalid.
A value in a structure member is invalid.
An operation failed because an attempt to acquire heap memory failed.
A read error occurred while reading from the EVM daemon connection.
A write error occurred while writing to the EVM daemon connection.
An error occurred on the EVM connection. Invoke
to destroy the connection.
A timeout period expired.
The current operation was interrupted by receipt of a signal.
One or more messages is queued for sending to the EVM daemon.
ERRORS
The value of is not set.
FILES
Default pathname for the domain socket.
SEE ALSO
Functions
connect(2), select(2), socket(2).
Routines
EvmConnControl(3), EvmConnCreate(3), EvmConnDestroy(3), EvmEvent‐
Post(3).
Event Management
EVM(5).
Event Callback
EvmCallback(5).
Event Connection
EvmConnection(5).
EVM Events
EvmEvent(5).
EvmConnCheck(3)