Posted by jpluimers on 2020/12/16
Learned TWO things at once Mark Longair and VonC at [WayBack] git – Hard reset of a single file – Stack Overflow :
You can use the following command:
git checkout HEAD -- my-file.txt… which will update both the working copy of
my-file.txtand its state in the index with that from HEAD.
--basically means: treat every argument after this point as a file name. More details in this answer. Thanks to VonC for pointing this out.
Related:
Posted in Development, DVCS - Distributed Version Control, git, Software Development, Source Code Management | Leave a Comment »
Posted by jpluimers on 2020/12/16
On my list of things to try: [WayBack] Spinettaro’s Blog: Delphi Flux application architecture.
It is about a Delphi implementation of the Facebook Flux application architecture.
Related:
Via: [WayBack] Delphi Flux application architecture A good application architecture Finding a good application architecture is not easy, but defining an architecture f… – Daniele Spinetti – Google+
Note that by using the [WayBack] CodeRage 2018 Replay | Embarcadero Academy, you are disallowed using any of what you learn in a commercial way.
Embarcadero evangelists told the public that for the Community Edition, similar terms would not be upheld, but then the sales department started sending out nasty emails to people registering Community Edition using their work email address.
[WayBack] https://www.embarcaderoacademy.com/p/terms:
under this license you may not:
- modify or copy the materials;
- use the materials for any commercial purpose, or for any public display (commercial or non-commercial);
- attempt to decompile or reverse engineer any software contained on the School’s web site;
- remove any copyright or other proprietary notations from the materials; or
- transfer the materials to another person or ‘mirror’ the materials on any other server.
–jeroen
Posted in Delphi, Development, JavaScript/ECMAScript, Scripting, Software Development, Systems Architecture, TypeScript | Leave a Comment »
Posted by jpluimers on 2020/12/16
Multi-threading is hard, knowing your primitives is important, but Embarcadero documentation is always far from complete, leading to [WayBack] System.SyncObjs.TLightweightSemaphore.Create: Please simply explain to me the parameters of this constructor, especially first, AInitialCount… – Jacek Laskowski – Google+
The concept of semaphores is universal (the free book [WayBack] The Little Book of Semaphores – Green Tea Press is great), but the implementation/wrapping can slightly differ, so on the [Archive.is] XE introduced TLightweightSemaphore.Create parameters:
Semaphore is used to allow ‘counted’ access. It allows access to as much owners as it has maximum count. If you wait on a semaphore (
WaitFor) and wait succeeds, the semaphore’s count is decremented. When it drops to 0, no newWaitwill succeed.When you call
Release, the semaphore’s count is incremented which allows somebody else to own the semaphore.Parameters simply set the initial state for this count and maximum value of the counter. Usually you’ll both set to the same value.
If you intend to use semaphores, read this. Great book.
The Little Book of Semaphores – Green Tea Pressgreenteapress.com
I know (theoretically) how a semaphore works. I even used this semaphore class in production code.
I want to create as many threads as there are cores in the processor (+ 1 additional, little loaded).fCoreController := TLightweightSemaphore.Create(TThread.ProcessorCount, TThread.ProcessorCount + 1);But now it turned out that customers who have CPUs with one core (yes, there are those), this code blocks the remaining threads. And I am looking for a reason, maybe I misunderstand this semaphore. What doesAInitialCountmean?ps. Delphi Seattle
AInitialCount is the number of entires a semaphore has left when created. If that is one less thanAMaxCountthat means you already gave one entry away. I just do a wild guess and say that you might do a Wait on the created semaphore shortly after creating it and in some other thread as well but since for one CPU yourAInitialCountis only 1, one of them will block – possibly you created a deadlock situation here.Semaphor.WaitFor) and I want to have as many threads as there are cores (+1 additional) then how should I createTLightweightSemaphoreobject?TThread.ProcessorCount + 1
–jeroen
Posted in Delphi, Development, Multi-Threading / Concurrency, Software Development | Leave a Comment »
The Wiert Corner - irregular stream of stuff 