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Wrapping synchronous code into asynchronous call
... in ASP.NET application, that consumes quite a lot of time to complete. A call to this method might occur up to 3 times during one user request, depending on the cache state and parameters that user provides. Each call takes about 1-2 seconds to complete. The method itself is synchronous call to the...
What is the use case of noop [:] in bash?
... to do.
while keep_waiting; do
: # busy-wait
done
The : builtin dates all the way back to the Thompson shell, it was present in Unix v6. : was a label indicator for the Thompson shell's goto statement. The label could be any text, so : doubled up as a comment indicator (if there is no goto comm...
The 'Access-Control-Allow-Origin' header contains multiple values
...rties.Settings.Default.Cors, "", ""))
as well as
app.UseCors(CorsOptions.AllowAll);
on the server. This results in two header entries. Just use the latter one and it works.
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Is file append atomic in UNIX?
...ger (linux seems to have it set to 4096).
This assume that you're talking all fully POSIX-compliant components. For instance, this isn't true on NFS.
But assuming you write to a log file you opened in 'O_APPEND' mode and keep your lines (including newline) under 'PIPE_BUF' bytes long, you should ...
How do you pass arguments to define_method?
... your defined method accepts arguments. When you define a method you're really just nicknaming the block and keeping a reference to it in the class. The parameters come with the block. So:
define_method(:say_hi) { |other| puts "Hi, " + other }
...
Error type 3 Error: Activity class {} does not exist
...the Build directory
Restarted Android Studio
Rebuild the Project
Run
Optionally (Go to the files menu on android, click on "Invalidate Caches / Restart..." uninstall the app on your phone and try again)
And everything worked fine!
I think the key is to restart your IDE.
Hope this helps you or a...
Why does my application spend 24% of its life doing a null check?
...t store a copy of the bytes in RAM. An important one is the L1 cache, typically 16 kilobytes for data and 16 kilobytes for instructions. Small, allowing it to be close to the execution engine. Reading bytes from the L1 cache typically takes 2 or 3 CPU cycles. Next up is the L2 cache, bigger and slow...
Why does Apple recommend to use dispatch_once for implementing the singleton pattern under ARC?
...
dispatch_once() is absolutely synchronous. Not all GCD methods do things asynchronously (case in point, dispatch_sync() is synchronous). The use of dispatch_once() replaces the following idiom:
+ (MyClass *)sharedInstance {
static MyClass *sharedInstance;
@synchr...
Update R using RStudio
...
You install a new version of R from the official website.
RStudio should automatically start with the new version when you relaunch it.
In case you need to do it manually, in RStudio, go to :Tools -> options -> General.
Chec...
Are (non-void) self-closing tags valid in HTML5?
...
In HTML 4, <foo / (yes, with no > at all) means <foo> (which leads to <br /> meaning <br>> (i.e. <br>&gt;) and <title/hello/ meaning <title>hello</title>). This is an SGML rule that browsers did a very poor job of su...