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Questions tagged [protocols]

A common means for (un)related objects to communicate with each other.

5211 questions
338
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18 answers

Get protocol, domain, and port from URL

I need to extract the full protocol, domain, and port from a given URL. For example: https://localhost:8181/ContactUs-1.0/contact?lang=it&report_type=consumer >>> https://localhost:8181
yelo3
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8 answers

How do I create my own URL protocol? (e.g. so://...)

I have seen: http://www... ftp://blah.blah... file://blah.blah... unreal://blah.blah... mailto://blah.blah... What is that first section where you see http and the like called? Can I register my own?
Michael Beck
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3 answers

Difference between Pragma and Cache-Control headers?

I read about Pragma header on Wikipedia which says: "The Pragma: no-cache header field is an HTTP/1.0 header intended for use in requests. It is a means for the browser to tell the server and any intermediate caches that it wants a fresh…
saplingPro
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13 answers

Difference between TCP and UDP?

What is the difference between TCP and UDP? I know that TCP is used in the case of non-time critical applications, and UDP is used for games or applications that require fast transmission of data. I know that TCP is used for HTTP, HTTPs, FTP, SMTP,…
user749414
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2 answers

Simple explanation of clojure protocols

I'm trying to understand clojure protocols and what problem they are supposed to solve. Does anyone have a clear explanation of the whats and whys of clojure protocols?
yazz.com
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2 answers

Cast an instance of a class to a @protocol in Objective-C

I have an object (a UIViewController) which may or may not conform to a protocol I've defined. I know I can determine if the object conforms to the protocol, then safely call the method: if([self.myViewController…
Ford
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100
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8 answers

binary protocols v. text protocols

does anyone have a good definition for what a binary protocol is? and what is a text protocol actually? how do these compare to each other in terms of bits sent on the wire? here's what wikipedia says about binary protocols: A binary protocol is a…
der_grosse
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How to require that a protocol can only be adopted by a specific class

I want this protocol: protocol AddsMoreCommands { /* ... */ } only to be adopted by classes that inherit from the class UIViewController. This page tells me I can specify that it is only adopted by a class (as opposed to a struct) by…
emrys57
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4 answers

How do I register a custom URL protocol in Windows?

How do I register a custom protocol with Windows so that when clicking a link in an email or on a web page my application is opened and the parameters from the URL are passed to it?
lukeck
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1 answer

Can a category implement a protocol in Objective C?

I have a category on NSDate and it would be convenient if it could implement a protocol I previously created. Is this possible? what's the correct syntax for this?
cfischer
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How can I send and receive WebSocket messages on the server side?

How can I send and receive messages on the server side using WebSocket, as per the protocol? Why do I get seemingly random bytes at the server when I send data from the browser to the server? It the data encoded somehow? How does the framing work…
pimvdb
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9 answers

Protocol func returning Self

I have a protocol P that returns a copy of the object: protocol P { func copy() -> Self } and a class C that implements P: class C : P { func copy() -> Self { return C() } } However, whether I put the return value as Self I get…
aeubanks
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What is the difference between DTR/DSR and RTS/CTS flow control?

What's the difference between DTR/DSR and RTS/CTS hardware flow control? When is each one used? Why do we need more than one kind of hardware flow control? :)
Gili
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13 answers

How to detect browser's protocol handlers?

I have created a custom URL protocol handler. http:// mailto:// custom:// I have registered a WinForms application to respond accordingly. This all works great. But I would like to be able to gracefully handle the case where the user doesn't have…
Chris Craft
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4 answers

Why I can't use let in protocol in Swift?

I have a doubt about protocols in Swift about the use of var and the keywords { get set }. From Apple documentation: If a protocol requires a property to be gettable and settable, that property requirement cannot be fulfilled by a constant stored…
Massimo Polimeni
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