Hello I am new in MSMQ,
having some C++ components I want to connect them via Microsoft Message Queue.
Using the function from https://msdn.microsoft.com/en-us/library/ms711416(v=vs.85).aspx. I want to create a new Message Queue.
This function I call with:
SECURITY_DESCRIPTOR securityDescriptor;
CreateSecurityDescriptor(&securityDescriptor);
WCHAR wszOutFormatName[256];
DWORD dwOutFormatNameLength;
CreateMSMQQueue(L"DIRECT=OS:.\\PRIVATE$\\MyQueue", &securityDescriptor, wszOutFormatName, &dwOutFormatNameLength);
CreateSecurityDescriptor creates as the name says a Default SecurityDescriptor. I can post the code if needed.
But the creating fails with the error code MQ_ERROR_ILLEGAL_QUEUE_PATHNAME. Which means:
PROPID_Q_PATHNAME contains an illegal Message Queuing path name string.
What is wrong with L"DIRECT=OS:.\\PRIVATE$\\MyQueue" ?
I got from https://msdn.microsoft.com/en-us/library/ms700996(v=vs.85).aspx
I am grateful for any help.
You can only reference an existing queue with a format name.
You cannot create a new queue with one.
Use a path name instead.
Difference between Path name and Format name when accessing MSMQ queues
Related
I'm trying to send a large block of data between applications by sending a control message over DBus from one to the other requesting a Unix file descriptor. I have it so that the client can request this, the server creates a DBus message that includes a UnixFDList, and the client receives a reply message but it doesn't contain anything. On the server side in Vala the DBusConnection object is setup using register_object, unfortunately the Vapi hides the DBusInterfaceVTable parameter that all the C examples use that would let me specify a delegate for method calls. I've tried to use register_object_with_closures instead but I can't seem to get that to work and the Closure object in Vala is woefully undocumented.
It seems to me that I need one of these methods in order to receive the message from the DBusMethodInvocation object that you get from a call to the DBusInterfaceMethodCallFunc delegate, with that you can create a reply message. Is there a way to either specify a closure class that works with register_object_with_closures, or a way to specify a DBusInterfaceVTable object as part of the service data?
I know that one option is to just create the service in C, but I'd rather figure out and understand how this works in Vala.
Vala uses UnixFDList internally for methods that contain a parameter of type GLib.UnixInputStream, GLib.UnixOutputStream, GLib.Socket, or GLib.FileDescriptorBased.
Example:
[DBus(name="eu.tiliado.Nuvola")]
public interface MasterDbusIfce: GLib.Object {
public abstract void get_connection(
string app_id,
string dbus_id,
out GLib.Socket? socket,
out string? token) throws GLib.Error;
}
I've implemented a solution to parse Email Files (.eml) into objects using Mime4J. The process parses an email file, create an object and write a new file to disk.
I was wondering if is possible to send the MimeMessage of Mime4J through Transport.send(mimeMessage) instead to create a new file.
The simplest approach would be to use the Mime4J Message.writeTo method to write the message to a ByteArrayOutputStream, then wrap the byte array with a ByteArrayInputStream and use that to construct a JavaMail MimeMessage object.
A more complex but more efficient approach would be to create a class that subclasses MimeMessage and delegates most of the methods to the corresponding methods on the Mime4J Message object.
I am using the following code to generate a message ACK:
public static Message process(Message in) throws Exception {
ADTReceiverQueue.getInstance().submit(in);
Message out = in.generateACK();
return out;
}
}
This generates the following warning:
FileBasedGenerator - Could not write ID to file /var/lib/tomcat7/./id_file, going to use internal ID generator. /var/lib/tomcat7/./id_file (Permission denied)
I can obviously set permissions to remove the warning, however I am wondering how to tell Hapi to use the internal ID generator or possibly a generator where the ID is stored in a database?
HAPI provides the IDGenerator interface to provide different implementations of ID generation. If you look at the JavaDoc for that class you'll find a bunch of different options for doing ID generation and you could certainly roll your own too.
To actually set the ID generator is easy enough, you just need to set it on the ParserConfiguration which is stored in the context.
HapiContext ctx = new DefaultHapiContext();
ctx.getParserConfiguration().setIdGenerator(new FileBasedHiLoGenerator());
If you use that context object to create your server then you're done, or if you didn't you can explicitly set it on the received message before generating an ACK.
in.setParser(ctx.getPipeParser());
-James
I use following command to locate EFI_USER_MANAGER_PROTOCOL:
Status = gBS->LocateHandle(ByProtocol, &gEfiUserManagerProtocolGuid, NULL, &bufferSizeu, handlesu);
I get EFI_ERROR - EFI_NOT_FOUND.
Now i try to install protocol and then open protocol:
Status = gBS->InstallMultipleProtocolInterfaces (&ImageHandle, &gEfiUserManagerProtocolGuid, NULL, NULL);
Protocol open successfully and i try to call function current():
Status = users->Current(users, &User);
Computer freezes and no show any errors.
How can I fix it?
To fix the problem you need to check how you call InstallMultipleProtocolInterfaces - it looks like you did not provide the protocol instance (actually you provided NULL). Therefore when you locate the protocol instance you locate what you placed there, i.e. NULL, so your "users" variable is NULL and the system hangs when you use it.
Please find in UEFI spec the description of InstallMultipleProtocolInterfaces:
The first item (after Handle) is always a pointer to the protocol’s GUID, and the second item is always a pointer to the protocol’s interface. These pairs are used to call the boot service InstallProtocolInterface() to add a protocol interface to Handle.
I would do something like:
Status = gBS->InstallMultipleProtocolInterfaces (
&ImageHandle,
&gEfiUserManagerProtocolGuid,
&mUserManager,
NULL);
where mUserManager would be your protocol interface structure. Since you own the protocol interface, you can verify if the address of the located protocol points to the actual location of the structure.
I'm building a client using dns-sd api from Bonjour. I notice that there is a flag called kDNSServiceFlagsShareConnection that it is used to share the connection of one DNSServiceRef.
Apple site says
For efficiency, clients that perform many concurrent operations may want to use a single Unix Domain Socket connection with the background daemon, instead of having a separate connection for each independent operation. To use this mode, clients first call DNSServiceCreateConnection(&MainRef) to initialize the main DNSServiceRef. For each subsequent operation that is to share that same connection, the client copies the MainRef, and then passes the address of that copy, setting the ShareConnection flag to tell the library that this DNSServiceRef is not a typical uninitialized DNSServiceRef; it's a copy of an existing DNSServiceRef whose connection information should be reused.
There is even an example that shows how to use the flag. The problem i'm having is when I run the program it stays like waiting for something whenever I call a function with the flag. Here is the code:
DNSServiceErrorType error;
DNSServiceRef MainRef, BrowseRef;
error = DNSServiceCreateConnection(&MainRef);
BrowseRef = MainRef;
//I'm omitting when I check for errors
error = DNSServiceBrowse(&MainRef, kDNSServiceFlagsShareConnection, 0, "_http._tcp", "local", browse_reply, NULL);
// After this call the program stays waiting for I don't know what
//I'm omitting when I check for errors
error = DNSServiceBrowse(&BrowseRef, kDNSServiceFlagsShareConnection, 0, "_http._tcp", "local", browse_reply, NULL);
//I'm omitting when i check for errors
DNSServiceRefDeallocate(BrowseRef); // Terminate the browse operation
DNSServiceRefDeallocate(MainRef); // Terminate the shared connection
Any ideas? thoughts? suggestion?
Since there are conflicting answers, I dug up the source - annotations by me.
// If sharing...
if (flags & kDNSServiceFlagsShareConnection)
{
// There must be something to share (can't use this on the first call)
if (!*ref)
{
return kDNSServiceErr_BadParam;
}
// Ref must look valid (specifically, ref->fd)
if (!DNSServiceRefValid(*ref) ||
// Most operations cannot be shared.
((*ref)->op != connection_request &&
(*ref)->op != connection_delegate_request) ||
// When sharing, pass the ref from the original call.
(*ref)->primary)
{
return kDNSServiceErr_BadReference;
}
The primary fiels is explained elsewhere:
// When using kDNSServiceFlagsShareConnection, there is one primary _DNSServiceOp_t, and zero or more subordinates
// For the primary, the 'next' field points to the first subordinate, and its 'next' field points to the next, and so on.
// For the primary, the 'primary' field is NULL; for subordinates the 'primary' field points back to the associated primary
The problem with the question is that DNSServiceBrowse maps to ref->op==browse_request which causes a kDNSServiceErr_BadReference.
It looks like kDNSServiceFlagsShareConnection is half-implemented, because I've also seen cases in which it works - this source was found by tracing back when it didn't work.
Service referenses for browsing and resolving may unfortunately not be shared. See the comments in the Bonjour documentation for the kDNSServiceFlagsShareConnection-flag. Since you only browse twice I would just let them have separate service-refs instead.
So both DNSServiceBrowse() and DNSServiceResolve() require an unallocated service-ref as first parameter.
I can't explain why your program chokes though. The first DNSServiceBrowse() call in your example should return immediately with an error code.
Although an old question, but it should help people looking around for answers now.
The answer by vidtige is incorrect, the may be shared for any operation, provided you pass the 'kDNSServiceFlagsShareConnection' flag along with the arguments. Sample below -
m_dnsrefsearch = m_dnsservice;
DNSServiceErrorType mdnserr = DNSServiceBrowse(&m_dnsrefsearch,kDNSServiceFlagsShareConnection,0,
"_workstation._tcp",NULL,
DNSServiceBrowseReplyCallback,NULL);
Reference - http://osxr.org/android/source/external/mdnsresponder/mDNSShared/dns_sd.h#0267