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DCEThreads
DCEThreads is an implementation of POSIX Draft 4 threads. DCE Stands for "Distributed Computing Environment" DCEThreads allowed users to create multiple avenues of execution in a single process. It is based on pthreads interface. History DCE/RPC was under development, but the POSIX committee had not finalised POSIX threads at the time. The Open Group had to make a decision about which to use, and the final POSIX threads were different from their selection. POSIX Draft 4 threads were limited to begin with (the final standard fixed these). Microsoft adopted DCE/RPC wholesale in Windows NT as MSRPC and also in Distributed Component Object Model, DCOM. Most of the stability and reliability problems that programmers associate with DCOM services - especially memory leaks, exception handling problems and thread cancellation stability issues - can be traced back to the use of POSIX Draft 4 threads. DCE/RPC is sufficiently complex that the issue of updating it to solve and modernise the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
POSIX
The Portable Operating System Interface (POSIX) is a family of standards specified by the IEEE Computer Society for maintaining compatibility between operating systems. POSIX defines both the system- and user-level application programming interfaces (APIs), along with command line shells and utility interfaces, for software compatibility (portability) with variants of Unix and other operating systems. POSIX is also a trademark of the IEEE. POSIX is intended to be used by both application and system developers. Name Originally, the name "POSIX" referred to IEEE Std 1003.1-1988, released in 1988. The family of POSIX standards is formally designated as IEEE 1003 and the ISO/IEC standard number is ISO/IEC 9945. The standards emerged from a project that began in 1984 building on work from related activity in the ''/usr/group'' association. Richard Stallman suggested the name ''POSIX'' (pronounced as ''pahz-icks,'' as in ''positive'', not as ''poh-six'') to the IEEE instead of former ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DCE/RPC
DCE/RPC, short for "Distributed Computing Environment / Remote Procedure Calls", is the remote procedure call system developed for the Distributed Computing Environment (DCE). This system allows programmers to write distributed software as if it were all working on the same computer, without having to worry about the underlying network code. History DCE/RPC was commissioned by the Open Software Foundation in a "Request for Technology" (1993 David Chappell). One of the key companies that contributed was Apollo Computer, who brought in NCA - "Network Computing Architecture" which became Network Computing System (NCS) and then a major part of DCE/RPC itself. The naming convention for transports that can be designed (as architectural plugins) and then made available to DCE/RPC echoes these origins, e.g. ncacn_np ( SMB Named Pipes transport); ncacn_tcp (DCE/RPC over TCP/IP) and ncacn_http to name a small number. DCE/RPC's history is such that it's sometimes cited as an example of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Open Group
The Open Group is a global consortium that seeks to "enable the achievement of business objectives" by developing "open, vendor-neutral technology standards and certifications." It has over 840 member organizations and provides a number of services, including strategy, management, innovation and research, standards, certification, and test development. It was established in 1996 when X/Open merged with the Open Software Foundation. The Open Group is the certifying body for the UNIX trademark, and publishes the Single UNIX Specification technical standard, which extends the POSIX standards. The Open Group also develops and manages the TOGAF® standard, which is an industry standard enterprise architecture framework. Members The over 840 members include a range of technology vendors and buyers as well as government agencies, including, for example, Capgemini, Fujitsu, HPE, Orbus Software, IBM, Huawei, Philips, the U.S. Department of Defense, and NASA. There is no obligation on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MSRPC
Microsoft RPC (Microsoft Remote Procedure Call) is a modified version of DCE/RPC. Additions include partial support for UCS-2 (but not Unicode) strings, implicit handles, and complex calculations in the variable-length string and structure paradigms already present in DCE/RPC. Example The DCE 1.0 reference implementation only allows such constructs as , or possibly . MSRPC allows much more complex constructs such as and even , a common expression in DCOM IDL files. Use MSRPC was used by Microsoft to seamlessly create a client/server model in Windows NT, with very little effort. For example, the Windows Server domains protocols are entirely MSRPC based, as is Microsoft's DNS administrative tool. Microsoft Exchange Server 5.5's administrative front-ends are all MSRPC client/server applications, and its MAPI was made more secure by "proxying" MAPI over a set of simple MSRPC functions that enable encryption at the MSRPC layer without involving the MAPI protocol. History MSRPC is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distributed Component Object Model
Distributed Component Object Model (DCOM) is a proprietary Microsoft technology for communication between software components on networked computers. DCOM, which originally was called "Network OLE", extends Microsoft's COM, and provides the communication substrate under Microsoft's COM+ application server infrastructure. The extension COM into Distributed COM was due to extensive use of DCE/RPC (Distributed Computing Environment/Remote Procedure Calls) – more specifically Microsoft's enhanced version, known as MSRPC. In terms of the extensions it added to COM, DCOM had to solve the problems of: * Marshalling – serializing and deserializing the arguments and return values of method calls "over the wire". *Distributed garbage collection – ensuring that references held by clients of interfaces are released when, for example, the client process crashed, or the network connection was lost. *Combining significant numbers of objects in the client's browser into a single transmi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory Leak
In computer science, a memory leak is a type of resource leak that occurs when a computer program incorrectly manages memory allocations in a way that Computer memory, memory which is no longer needed is not released. A memory leak may also happen when an object (computer science), object is stored in memory but cannot be accessed by the running code (i.e. unreachable memory). A memory leak has symptoms similar to a number of other problems and generally can only be diagnosed by a programmer with access to the program's source code. A related concept is the "space leak", which is when a program consumes excessive memory but does eventually release it. Because they can exhaust available system memory as an application runs, memory leaks are often the cause of or a contributing factor to software aging. Consequences A memory leak reduces the performance of the computer by reducing the amount of available memory. Eventually, in the worst case, too much of the available memory may b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
