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How to run a program without an operating system?
...ystem running?
Can you create assembly programs that the computer can load and run at startup, e.g. boot the computer from a flash drive and it runs the program that is on the CPU?
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How to select all records from one table that do not exist in another table?
...: What is happening here?
A: Conceptually, we select all rows from table1 and for each row we attempt to find a row in table2 with the same value for the name column. If there is no such row, we just leave the table2 portion of our result empty for that row. Then we constrain our selection by picki...
How can I make the computer beep in C#?
...p().
// Default beep
Console.Beep();
You can also specify the frequency and length of the beep in milliseconds.
// Beep at 5000 Hz for 1 second
Console.Beep(5000, 1000);
For more information refer http://msdn.microsoft.com/en-us/library/8hftfeyw%28v=vs.110%29.aspx
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Is Integer Immutable
... isn't final, it can point to a different object.
– Sandman
Apr 6 '11 at 7:20
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Better way to check variable for null or empty string?
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// Function for basic field validation (present and neither empty nor only white space
function IsNullOrEmptyString($str){
return (!isset($str) || trim($str) === '');
}
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$.focus() not working
... focus from the dev console. If you run the following code in your console and then quickly click in your browser window after, you will see it focus the search box:
setTimeout(function() { $('input[name="q"]').focus() }, 3000);
As for your other one, the one thing that has given me trouble in th...
Java project in Eclipse: The type java.lang.Object cannot be resolved. It is indirectly referenced f
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This is an annoying Eclipse Bug which seems to bite now and then. See http://dev-answers.blogspot.de/2009/06/eclipse-build-errors-javalangobject.html for a possible solution, otherwise try the following;
Close the project and reopen it.
Clean the project (It will rebuild the bui...
Lost my schema.rb! Can it be regenerated?
...issues I stopped tracking schema.rb in git. Somehow I have stuffed this up and somewhere along the way my schema.rb file has disappeared.
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Rails: around_* callbacks
...api.rubyonrails.org/classes/ActiveRecord/Callbacks.html , but don't understand when the around_* callbacks are triggered in relation to before_* and after_* .
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Why are mutable structs “evil”?
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So if you change a copy you are changing only that copy, not the original and not any other copies which might be around.
If your struct is immutable then all automatic copies resulting from being passed by value will be the same.
If you want to change it you have to consciously do it by creating...