The other answers already correctly addressed what’s apparently your actual question: Does it mean I can or cannot modified the items in a dictionary while iterating over it? by explaining that thread safety has nothing to do with the issue, and in any case, no, you cannot modify a dict while iterating over it. However, … Read more
I’m no expert, but cppreference.com has what appears to me to be some pretty good information on volatile. Here’s the gist of it: Every access (both read and write) made through an lvalue expression of volatile-qualified type is considered an observable side effect for the purpose of optimization and is evaluated strictly according to the … Read more
How you approach this is going to depend a lot on how frequently you’re writing. If you’re writing a relatively small amount of text fairly infrequently, then just use a static lock and be done with it. That might be your best bet in any case because the disk drive can only satisfy one request … Read more
from __future__ import print_function print = lambda x: sys.stdout.write(“%s\n” % x) Is a nice cheap and dirty hack.
Because a try/finally block is the only way to guarantee that a segment of code is executed after another completes. You ask why not do this: public void function1(){ read.lock(); this.getSharedInt(); read.unlock(); } What happens when this.getSharedInt() throws an exception? Then your read.unlock() line will not be executed, causing program deadlock. Sure, it may be … Read more
Writing a thread safe code in Delphi involves the basic care you would have in any other language, which means to deal with race conditions. A race condition happens when different threads access the same data. A good way to deal with that is to declare an instance of TCriticalSection and wrap the dangerous code … Read more
Another solution for this case is to move a mutable reference to the item into the thread, even though mutability isn’t required. Since there can be only one mutable reference, the compiler knows that it’s safe to be used in another thread. use crossbeam; // 0.7.3 use std::cell::RefCell; fn main() { let mut val = … Read more
It’s not a common way to share a SqlConnection, and it should be used only under special uses cases. First, You’re true that resource pooling is a common pattern used to improve performance when working with sockets, network streams, web services… But especially for SqlConnection, you don’t have to worry about this because the framework … Read more
Well – best practice is that structs should always (except in a few very specific scenarios, and even then at risk) be immutable. And immutable data is always thread safe. So if you followed best practice and made this: struct Data { readonly int _number; public int Number { get { return _number; } } … Read more
Monkey patch the host, user and password methods of ActiveResource::Base class: class ActiveResource::Base # store the attribute value in a thread local variable class << self %w(host user password).each do |attr| define_method(attr) do Thread.current[“active_resource.#{attr}”] end define_method(“#{attr}=”) do |val| Thread.current[“active_resource.#{attr}”] = val end end end end Now set the credentials in every request class ApplicationController < … Read more