DCEThreads
The topic of this article may not meet Wikipedia's general notability guideline. (October 2011) |
DCEThreads is an implementation of POSIX Draft 4 threads. DCE Stands for "Distributed Computing Environment" [1] DCEThreads allowed users to create multiple avenues of execution in a single process.[2] It is based on pthreads interface.[3]
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 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 POSIX Draft 4 threading problem requires highly skilled and highly specific programming knowledge. Consequently, despite its capacities, the reference implementation of DCE/RPC has been held up due to a lack of information and resources.
The key difference between POSIX Draft 4 threads and the final POSIX threads specification, aside from a number of functions being interruptible where others are not, is thread cancellation. DCE/RPC utilises thread cancellation to propagate signals across the "Remote" of RPC, such that for example a client application terminating a thread results in its corresponding thread on the server also being terminated in the same way. The final POSIX specification does not include such sophisticated cancellation methodology, and, given the difficulties that the Unix vendors had in correctly implementing the POSIX threads specification, it was removed.
Recent developments
Linux, since the introduction of NPTL and the Linux 2.6 kernel, has proper support for thread cancellation.
Current use
DCEThreads now only realistically exists as an emulation layer.
References
- ^ "IBM Docs". IBM.
- ^ "dec95a1.pdf" (PDF). Archived from the original (PDF) on 2015-12-18. Retrieved 2021-02-10.
- ^ "What is DCE Threads?".
Content Disclaimer
Informasi ini disarikan dari Wikipedia dan disajikan kembali untuk tujuan edukasi. Konten tersedia di bawah lisensi CC BY-SA 3.0. Kami tidak bertanggung jawab atas ketidakakuratan data yang bersumber dari kontribusi publik tersebut.
- The information displayed on this website is sourced in part or in whole from Wikipedia and has been adapted for the purpose of restating it. We strive to provide accurate and relevant information, however:
- There is no guarantee of absolute accuracy. Wikipedia is an open, collaborative project that can be edited by anyone, so information is subject to change.
- It is not intended to constitute professional advice. The content displayed is for informational and educational purposes only. For important decisions (e.g., medical, legal, or financial), please consult a professional.
- Content copyright. Wikipedia is licensed under the Creative Commons Attribution-ShareAlike License (CC BY-SA). This means that content may be reused with appropriate attribution and shared under a similar license.
- Responsible use. Any risk arising from the use of information from this website is entirely the responsibility of the user.