Wikipedia:Reference desk/Archives/Computing/2014 September 1

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September 1

How to search for movies that move ?

I type a topic into a search engine, pick movies, and get what looks to be movies about that topic. But they are just slide shows instead. Is there a way to exclude those from the search results ? One complicating factor is that they may have movement, of a sort, if they pan the snapshots or zoom in on them. But that's not what I want, I want a full motion movie. Any ideas ? StuRat (talk) 04:05, 1 September 2014 (UTC)

I don't know, but I hope so, too. Even worse is when you think you're getting a movie, but after the ad stops, it's just a 1:34:23 long screenshot with an ad for a pirate site tacked on. Doesn't pan, doesn't zoom, doesn't do anything. No music. Just anger! YouTube owes me that 1:34:23 of my life back.

Sadly, I think the indexers just look at the file, host and keywords. If it says FLV or whatever, it's a movie to their puny robot brains. InedibleHulk (talk) 04:17, 1 September 2014 (UTC)

This is the kind of deep metadata that Google may actually be able to provide at some point in the future, especially given that they own Youtube. Look at the strides they've made on the Image search in the last year or two. But at the moment, no, I don't think there's a good way to find what you're looking for. Riffraffselbow (talk) (contribs) 12:38, 12 September 2014 (UTC)

Pre-compiled header files?

I noticed that my work computer's (Windows 7) hard drive is 43% full of "pre-compiled header files" (.pch) presumably created by Microsoft Visual Studio. What are these used for? Do I need them after successfully building my code? If not, then is there an easy way in Windows to automatically delete them? JIP | Talk 13:32, 1 September 2014 (UTC)

Does the MSDN article Creating Precompiled Header Files help? --Phil Holmes (talk) 14:03, 1 September 2014 (UTC)

In short, they are "cached" compiled files which are unlikely to change, and supposed to speed up large projects. You can delete these files, or just those which haven't been accessed recently, without any ill effects (unless you recompile the code which recreates them; they will reappear if you do ;) )

In my experience, the savings are minimal and sometimes negative; OTOH, compiling across networks does seem to save time, due to the slower data transfer in that case.

43% is a metric shitload of them, given the size of a Windows 7, or generally a post-XP Windows, partition. - ¡Ouch! (^{hurt me} / _{more pain}) 14:29, 1 September 2014 (UTC)

That there is a "metric shitload" of them is mostly because our application is big (I haven't counted, but the source code must run into several hundred thousand lines of code, if not over a million, and the total installed size of the compiled application is in the order of several gigabytes), and I have to maintain several different versions of it, as different customers have different licence agreements, which include different versions of the application. I'm just amazed that these pre-compiled header files take up way more space than the source code or the compiled application. JIP | Talk 19:06, 1 September 2014 (UTC)

Several gigabytes of code would explain the PCH bloat quite nicely, indeed.

...and I made an error in the unit conversion; it's only an imperial shitload. ;) - ¡Ouch! (^{hurt me} / _{more pain}) 06:46, 2 September 2014 (UTC)

PCH files will only help if you have two or more compilation units that start with exactly the same code (and are compiled with the same command-line options). To get the benefit you need to compile one of them with the generate-PCH option (-Yc), then compile the others with the use-PCH option (-Yu). In standard Visual Studio projects you put common headers in stdafx.h and #include that from all of your source files, and there's a dummy stdafx.cpp that also #includes it and gets compiled first. If your project isn't set up that way, and is (mis)configured to pass -Yc when building every file, that might explain the metric firkin of PCH files you're seeing. In that case they're not doing any good and are actually slowing down your build. -- BenRG (talk) 22:23, 1 September 2014 (UTC)