Tear-Down | project consists of building a heatmap of the Smashing

I am writing a Windows service in VB.Net that will go out to some devices and data log points of information. I am using a Background Worker to do that so the service itself is still responsive. I have a timer that runs every second and checks the minute component of the current time. Each time the minute component changes I check which devices need to be checked, some are every minute, some every 5, some every 10, etc. These processes can take a few seconds or over a minute (I only rerun the worker if it's not already running and log a error if the last process took longer then the data retrieval interval).

In my OnStop event for the service I want to make sure the workers all close down. I call CancelAsync on the worker and the worker checks for cancellation to hopefully exit cleanly (i.e., check cancelation, if false retrieve data, save data into database, loop).

My problem is I don't want to use a sleep statement as it will lock everything but I also don't want the service to never shut down. So for example I have this currently:

I'm trying to mock a simple function from the Linux standard library. strerror() returns the error message from an errno. This is my library with the function to mock:

I am trying to understand the TCP reset problem mentioned in RFC 7230: HTTP/1.1 Message Syntax and Routing, § 6.6:

6.6. Tear-down

The Connection header field (Section 6.1) provides a "close" connection option that a sender SHOULD send when it wishes to close the connection after the current request/response pair.

So HTTP/1.1 has persistent connections, meaning that multiple HTTP request/response pairs can be sent on the same connection.

A client that sends a "close" connection option MUST NOT send further requests on that connection (after the one containing "close") and MUST close the connection after reading the final response message corresponding to this request.

A server that receives a "close" connection option MUST initiate a close of the connection (see below) after it sends the final response to the request that contained "close". The server SHOULD send a "close" connection option in its final response on that connection. The server MUST NOT process any further requests received on that connection.

So the client signals that it will close the connection by adding the Connection: close header field to the last HTTP request, and it closes the connection only after it receives the HTTP response acknowledging that the server received the request.

A server that sends a "close" connection option MUST initiate a close of the connection (see below) after it sends the response containing "close". The server MUST NOT process any further requests received on that connection.

A client that receives a "close" connection option MUST cease sending requests on that connection and close the connection after reading the response message containing the "close"; if additional pipelined requests had been sent on the connection, the client SHOULD NOT assume that they will be processed by the server.

So the server signals that it will close the connection by adding the Connection: close header field to the last HTTP response, and it closes the connection. But it closes the connection only after receiving which message acknowledging that the client received the HTTP response?

If a server performs an immediate close of a TCP connection, there is a significant risk that the client will not be able to read the last HTTP response. If the server receives additional data from the client on a fully closed connection, such as another request that was sent by the client before receiving the server's response, the server's TCP stack will send a reset packet to the client; unfortunately, the reset packet might erase the client's unacknowledged input buffers before they can be read and interpreted by the client's HTTP parser.

So in the case where the server initiates the close of the connection, if the server fully closes the connection right after sending the HTTP response with a Connection: close header field to an initial HTTP request, then the client may not receive that HTTP response because it received a TCP reset packet response to a subsequent HTTP request that it sent after the initial HTTP request. But how can the TCP reset packet response to the subsequent HTTP request precede the HTTP response to the initial HTTP request?

To avoid the TCP reset problem, servers typically close a connection in stages. First, the server performs a half-close by closing only the write side of the read/write connection. The server then continues to read from the connection until it receives a corresponding close by the client, or until the server is reasonably certain that its own TCP stack has received the client's acknowledgement of the packet(s) containing the server's last response. Finally, the server fully closes the connection.

So in the case where the server initiates the close of the connection, the server only closes the write side of the connection right after sending the HTTP response with a Connection: close header field to an initial HTTP request, and it closes the read side of the connection only after receiving a subsequent corresponding HTTP request with a Connection: close header field or after waiting for a period long enough to assume that it received a TCP message acknowledging that the client received the HTTP response. But why would the client send a subsequent corresponding HTTP request with a Connection: close header field after receiving the HTTP response with a Connection: close header field, whereas paragraph 5 states: ‘A client that receives a "close" connection option MUST cease sending requests on that connection’?

It is unknown whether the reset problem is exclusive to TCP or might also be found in other transport connection protocols.

I have a component as follows:

I'm trying to write simple UnitTests for basic sorting algorithms. While using gtest, I'm running into this strange problem, where tests from different suites are merging:

I've exploring locust for our load testing requirements for Spark but stuck on some very basic tasks; documentation also seems very limited.

Stuck on how/where to write my setup & tear-down code that needs to run only once regardless of the number of users. Tried with below sample given in docs; but the code written under events.test_start doesn't run it seems as I'm unable to use attribute 'sc' anywhere under SparkJob class. Any idea how to access the spark instances created under on_test_start method in my SparkJob class?

So I got some code handling some simple tcp sockets using the SFML Library. Thereby a socket is created under the usage of SFML capabilities and returned from a function as an rvalue reference. An organizing function then passes this socket on ( to currently only be stored ) and signals its caller whether a socket was processed or not. This however does not work as expected.

I have tested the .decreaseInventory() manually in my main file so I know it works correctly but when I run a google test on it, it fails and gives me an error. How could I fix this?

Player class:

I do know that there is the BeforeAndAfter trait which allows us to perform setup and tear-down operations before and after every test of a suite.

Is there an alternative that either runs only before and after a suite or runs for selected tests?