Databases
StackOverflow2013
Postsdbo
POEnumPorts() returns strange error on some machines
Body
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POEnumPorts() returns strange error on some machines
    text
    copied!<p>I maintain an application that uses the win32 EnumPorts() function to help determine the set of serial ports installed on the computer. I have seen cases on some computers where the call to get this information fails with a GetLastError() code of 1722 (RPC server is unavailable). I assume that this has something to do with either registry settings or a required service being disabled but my search so far has been rather fruitless. Has anyonw else encountered this issue?</p> <p>In answer to Euro Micelli's comments. I am specifically attempting to fill a pick list that will allow the user to choose an available picklist. To begin with, I relied exclusively on EnumPorts() to provide me a list of potential serial port names. It has proven to be unreliable, however in several senses: It has not always provided the complete set of port names and, as I have recently seen, it can fail to function altogether when the "RPC service is unavailable". Why RPC is needed to find out what ports are available on the local machine is completely beyond me but there it is. This latter problem was the final straw. So far as relying completely on the list of names provided, i filter these names using the GetDefaultCommConfig() function to determine the exact nature of each of the names that I came up with.</p> <p>In my experience, the list of names provided by the previously mentioned registry key has been the most reliable method for getting port names. As a matter of fact, I can see the key get updated as I disable port drivers in the device device manager. Under normal experiences, I would agree with the assessment that relying upon a particular key is fraught with peril. In this case, however, M$ has never provided a decent mechanism to evaluate the names of available ports.</p> <p>I should point out that I have already replaced the call to EnumPorts() with an algorithm that scans the registry key: HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP\SERIALCOMM for serial port names. This should resolve the issue once my software is released. What I am after is pointers that can be given to customers who are using the released package at the present.</p>
 

Querying!

 
Guidance
An individual column

Larger individual text columns get their own page to allow for proper reading.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload