visual basic barcode printing s_value = new Singleton(); // This is what you'd ideally like to write in .NET

Maker qr codes in .NET s_value = new Singleton(); // This is what you'd ideally like to write

method simply calls Dispose . Some classes that offer the dispose pattern also offer a Close method for convenience; but the dispose pattern doesn t require this method . For example, the System.IO.FileStream class offers the dispose pattern, and this class also offers a Close method . Programmers find it more natural to close a file rather than dispose of a file . However, the System.Threading.Timer class doesn t offer a Close method even though it adheres to the dispose pattern .

fbChain = (Feedback) Delegate.Combine(fbChain, fb1);

In this section I ll describe a variation of the islands problem and a solution based on the group identi er concept. The problem at hand involves a table (call it T3) with two columns of interest one column represents a sequence of keys (call it id), and another column represents a status value (call it val). Run the following code to create a table called T3 and populate it with sample data:

If a worker thread sees that its local queue is empty, then the worker thread will attempt to steal a Task from another worker thread s local queue . Tasks are stolen from the tail of a local queue and require that a thread synchronization lock be taken, which hurts performance a little bit . Of course, the hope is that stealing rarely occurs, so this lock is taken rarely . If all the local queues are empty, then the worker thread will extract an item from the global queue (taking its lock) using the FIFO algorithm . If the global queue is empty, then the worker thread puts itself to sleep waiting for something to show up . If it sleeps for a long time, then it will wake itself up and destroy itself, allowing the system to reclaim the resources (kernel object, stacks, TEB) that were used by the thread . The thread pool will quickly create worker threads so that the number of worker threads is equal to the value pass to ThreadPool s SetMinThreads method . If you never call this method (and it s recommended that you never call this method), then the default value is equal to the number of CPUs that your process is allowed to use as determined by your process s affinity mask . Usually your process is allowed to use all the CPUs on the machine,5 so the thread pool will quickly create worker threads up to the number of CPUs on the machine . After this many threads have been created, the thread pool monitors the completion rate of work items and if items are taking a long time to complete (the meaning of which is not documented), it creates more worker threads . If items start completing quickly, then worker threads will be destroyed .

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hardware platform, you could redefine the capitalized versions so that they could match the data types on the original hardware. If your language isn t case sensitive, you ll have to differentiate the names by some means other than capitalization.

or Yahoo! Mail), your e-mail provider will have provided you with outgoing mail server details that you can supply to Net::SMTP, as follows: Net::SMTP.start('mail.your-domain.com') This line of code connects to the SMTP server on port 25 of mail.your-domain.com without using any username or password. If you need to, though, you can specify port number and other details. For example: Net::SMTP.start('mail.your-domain.com', 25, 'localhost', 'username', 'password', :plain) This example connects to the SMTP server at mail.your-domain.com using a username and password in plain text format. It identifies the client s hostname as localhost.

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// internal type as if it were a public type SomeInternalType sit = new SomeInternalType(); return sit; } }

There are some common programming scenarios that can potentially benefit from the improved performance possible with tasks . To simplify programming, the static System. Threading.Tasks.Parallel class encapsulates these common scenarios while using Task objects internally . For example, instead of processing all the items in a collection like this:

It runs for about 0.6 seconds to generate a sequence of 1,000,000 numbers. As I mentioned earlier, you can wrap the logic in a UDF. The value of this solution is that it does not use recursion, and therefore does not need to explicitly increase the MAXRECURSION limit with a hint. Such a hint cannot be speci ed in a UDF de nition, but this is of no concern in our case. The following code encapsulates the last solution s logic in a UDF: