  Data Overruns, Processing Data Input? 
 The Question is:
 
I am receiving the following message while using business software -
'%SYSTEM-W-DATAOVERUN, data overrun'.  I can find very little information on
this message.  The message is the result of holding in the Enter key for
about 5 secs.  I suspect that it is
the result of a buffer being over loaded.  However, I am completely clueless
as to where the buffer would be, and how to change the settings or increase
the size.  Any help in this matter would be greatly appreciated.  Thank you
in advance for any help.
 
 The Answer is:
 
  The application software is apparently unable to contend with the
  volume of user input, and the associated user input buffer within
  the application is being overrun.
 
  Contact the application vendor for assistance.  Alternatively, don't
  leave books or elbows or other objects pressing on keyboard keys.
 
  If you are maintaining the application, you will need to investigate
  the particular operation generating the error.  The input can be
  buffered and flow control used as necessary, the overrun of data
  can be discarded, the entire input can be ignored and a message
  generated, or any of various other application-specific behaviours
  that can be implemented.
 
  The ENTER key generates a single carriage return character, a
  carriage return followed by a line feed character, or a sequence
  of characters (Single shift 3 (SS3) followed by an M) depending
  on the current setting of the terminal.  Depending on the particular
  application, the ENTER key on the keypad may or may not be treated
  as an input terminator.
 
$ help/message dataoverun
 
 
 DATAOVERUN,  data overrun
 
  Facility:     SYSTEM, System Services
 
  Explanation:  This message occurs under the following conditions:
 
                o More data has been read or written into the user buffer
                  than the user buffer can hold.
 
                o Card reader data has been written into the controller
                  data buffer before the driver has been able to receive
                  previously sent data.
 
                o Continued attempts to use PTD$WRITE have resulted in data
                  loss because the terminal driver's type-ahead buffer is
                  full.
 
                If this message is associated with a status code returned by
                a request to a magnetic tape driver, the data block read is
                longer than the assigned buffer. On a read reverse operation,
                the first data read and stored in the buffer is the data that
                was nearest the end-of-tape marker when the operation began.
 
   User Action:  There are several possible user actions:
 
                o If there is too much data for the existing buffer, specify
                  a larger buffer.
 
                o If the problem occurred on a card reader operation,
                  resubmit the cards to the reader.
 
                o Turn on the alternate type-ahead buffer by using the DCL
                  command SET TERMINAL/ALTYPEAHD. Then increase the type-
                  ahead buffer size or the alternate type-ahead buffer size,
                  or both, by modifying the TTY SYSGEN parameters.
 
                o Wait until the driver is ready to receive input before you
                  resume writing data. For information on how to handle flow
                  control and the pseudoterminal, refer to the OpenVMS I/O
                  User's Reference Manual.
 
 
