I guess you can use file_get_contents, but is there something equivalent to http_get in hhvm? When I use google it points to hhvm docs which simply say it isn't supported.
Functions like this marked as missing in HHVM are usually because the function is part of an extension that hasn't been implemented yet. The PHP.net docs say it's part of a PECL extension, pecl_http -- which doesn't look to be on by default even in PHP5 (although of course it can be manually enabled). So definitely looks like the relevant extension hasn't been implemented in HHVM. If this function specifically is really important, and you can't find an adequate replacement, you can file a feature request issue on GitHub to let the team know you'd like it implemented. (Or send a pull request if you want to implement it yourself, of course!)
As for a replacement, I'd start with file_get_contents; if that doesn't meet your needs, I'm pretty sure the curl extension exists in HHVM. It's got a huge array of functionality, but you can almost certainly use it to do whatever you need.
Related
I want to simulate lidars. I saw that a class DepthSensor was mentioned in the documentation, but I have not found its actual implementation. For now, I am planning on using the RgbdSensor class and use only the height I need of the depth point cloud I receive to simulate my lidars.
Just to get your input on that, maybe I missed something, but is there a specific class for lidars, and how would you go about adding lidars to a simulation?
Thanks in advance,
Arnaud
You've discovered an anchronism in the code. There had previously been a lidar-like sensor (called DepthSensor). The extant documentation refers to that class. The class's removal should've been accompanied by a clean up of the documentation.
The approach you are taking is the expected approach given Drake's current state.
There has always been an intention to re-introduce a lidar-like sensor in Drake's current architecture. It simply hasn't been a high priority.
I'd recommend you proceed with what you're currently doing (lidar from depth images) but, at the same time, post an issue requesting a lidar-like query with specific focus on the minimum lidar-properties that you require. A discussion regarding how that would differ from what you can actually get from the depth images would better inform of us your unique needs and how to prioritize it. (You can also indicate more advanced features that you need less but would be good to have, of course).
As for the question: how would you go about adding lidars?
That's problematic. Ideally, what you would need is ray-casting ability. The intent is for QueryObject to support such a query, but it hasn't happened yet. (It's certainly the underlying technology we'd have used to implement a LidarSensor.) In the absence of that kind of functionality, you'd essentially have to do it yourself in the most horrible, tedious way imaginable. I'd go so far as to suggest that it's not feasible with the current API.
Recently i caught with the a thought of changing the implementation of method after deployment
When i googled about objective c runtime and all, came to know about method swizzling methodExchangeImplementations etc.
I know that it could be possible by https://rollout.io/
But my thought is how to do Hot Patching by myself for simple things.
my idea is injecting the code using webservice call.
Webservice should give a replacement for particular method.
That string has to be converted to executable code
What i want to know is ...
How to inject the code in existing method of enterprise application.
For ex:
Consider this method in objective c
-(void)fetchTheResult{
// some code lines
}
After deployment i would like to change the method implementation to
-(void)fetchTheresult{
NSLog(#"test log");
//some Code lines
//some more lines
}
Please guide me the way to achieve this
This is a big question and you've some research to do to figure out an answer. Here as some things you can look into:
First you've referenced Rollout, you could follow the same idea and send your update as JavaScript. You'll need to study how to call JavaScript, swizzle methods, and probably dynamically add methods - more on that in a moment.
An alternative you can investigate is dynamic library loading - you can open, and call code in, a library which your app loads at runtime. So you could look at sending your update as a library. You'll still need to do method swizzling and probably dynamically add methods...
As well as method swizzling you may find you need to dynamically add methods - e.g. so you have something to swap the existing implementation to. A good place to find out how to do that is Mike Ash's writings on KVO - go DuckDuckGo (or Google)
HTH
It is not as easy as you think, at least in Objective C and other similar compiled languages. This kind of runtime changes to the code is only possible in interpreted languages like Javascript.
The basic problem is, the apps are not allowed to change the executable files themselves. The apps on iOS and Android run in a sandboxed environment, and thus have access to limited disk locations only.
Also, after compiling the code, the code does not know where the part of code is converted and stored in machine language. You have to understand the basics of compilers to understand this. There are heavy optimisations happening to your code during this process.
Sorry for the generalized question...I have been hunting for a long time and haven't found anything I can use or easily adapt yet. I'd really appreciate any pointers!
I'm building a reference app that will contain several textbooks in plain-text format. I want the user to be able to perform a search, and get a table back with a list of results. I have a working prototype, but the search logic that I wrote isn't all that smart and it's been hell trying to make it better.
This is obviously a fairly common problem so I'm looking for a tool that I could adapt to the task. So far I've found Lucene (http://vafer.org/blog/20090107014544/) and Locayta (http://www.locayta.com/iOS-search-engine/locayta-search-mobile/)
Lucene appears to have been last updated for iOS 2...I don't even know if I'll be able to rework it myself. Maybe.
Locayta would probably work great, but a commercial license is $1,000 and I may not soon recoup that with this app, as it's a niche market.
Thanks!
We stumbled upon the same predicament where I work, and have yet to decide on a solution.
Locayta seems promising, but barring that, I've looked into SQLite's FTS3/FTS4 as well.
The only issue seemed the lack of a way to match partial words. It's easy to search for fields that contain whole words (eg. "paper" matches "printer paper", "paper punch", and "sketch paper"), or words that start with something (eg. "bi*" matches "binder", and "bicycle"), but there's no built in way to match a suffix.
If you don't require that functionality, FTS3/FTS4 might work.
I see you mentioned in the follow-up that your SQLite didn't recognize FTS3(), and I had the same issue at first.
Apparently it's not bundled into the iOS version by default, instead you have to download the SQLite3 amalgamation, and include it in the project manually. As found at is FTS available in the iOS build of SQLite?
Also note, the SQLITE_ENABLE_FTS3 variable is not enabled by default, you just have to add it to the configuration as detailed at http://www.sqlite.org/fts3.html#section_2
Hope this helps.
If you can translate plain C code to iOS Objective-C, then Apache Lucy (a loose "C" port of Lucene) might be worth a look.
Is it possible to make a system call, such as executing ls -la, and use the result in your app?
Usually when someone says system call they mean calling into the kernel through one of the defined entry points. While its technically possible on iPhone, you are always better of going through the libSystem shims because the call interface is probably not stable (it isn't on Mac OS X for instance). I doubt Apple would like it if you did that, but I suspect no one as really thought about it much and they are unlikely to notice.
I don't think that is what you mean though. I think you want to use ISO/IEC 9899:1990 (C90) C libraray function "system". The answer to that is no, you can't.
Sadly syscall.h under iOS is a private api. While you can use it in private applications Apple will not allow you to use the syscall() API for App Store submissions unfortunately.
I'm using an application (an instant messenger) which is not very popular. I'm trying to find the protocol that it uses. I know it's using TCP/IP but I want to find out all the commands that it is sending to the server and receiving from the server.
I tried a couple of sniffers, but they can not recognize this application by name and more over all I got was some unrelated hexadecimal codes.
Is there any idea how I can find the application's specifications?
(Please note: I googled it and found nothing and also there is no documentation by the author.)
There are generally two approaches to reverse engineering something like this:
You could try disassembling it with a tool like IDA PRO.
You could try sniffing its traffic with a tool like Wireshark
Either way, it's likely to be a LOT of work.
Wireshark will tell you the protocol. The fact that you cannot read the messages in clear text on the wire is a good thing, isn't it?