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What is null in Java?
...here is no type which null is an instanceof.
15.20.2 Type Comparison Operator instanceof
RelationalExpression:
RelationalExpression instanceof ReferenceType
At run time, the result of the instanceof operator is true if the value of the RelationalExpression is not null and the reference ...
How to declare a structure in a header that is to be used by multiple files in c?
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if this structure is to be used by some other file func.c how to do it?
When a type is used in a file (i.e. func.c file), it must be visible. The very worst way to do it is copy paste it in each source file needed it.
The right way is putting it ...
Force browser to download image files on click
I need the browser to download the image files just as it does while clicking on an Excel sheet.
14 Answers
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How do I update the notification text for a foreground service in Android?
I have a foreground service setup in Android. I would like to update the notification text. I am creating the service as shown below.
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Initializing a list to a known number of elements in Python [duplicate]
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The first thing that comes to mind for me is:
verts = [None]*1000
But do you really need to preinitialize it?
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How can I get a side-by-side diff when I do “git diff”?
When I type "git diff", I'd like to see a side-by-side diff, like with "diff -y", or like to display the diff in an interactive diff tool like "kdiff3". How can this be done?
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Possible reasons for timeout when trying to access EC2 instance
I cannot SSH into my instance - Operation timed out. What could be the reasons why, and what can I do to resolve it? Rebooting normally takes a long time to take effect, and might just makes things worst
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How can I change my default database in SQL Server without using MS SQL Server Management Studio?
...d a database from SQL Server, however it turns out that my login was set to use the dropped database as its default. I can connect to SQL Server Management Studio by using the 'options' button in the connection dialog and selecting 'master' as the database to connect to. However, whenever I try to...
How to programmatically empty browser cache?
I am looking for a way to programmatically empty the browser cache. I am doing this because the application caches confidential data and I'd like to remove those when you press "log out". This would happen either via server or JavaScript. Of course, using the software on foreign/public computer is s...
Pass all variables from one shell script to another?
...at the other script could modify variables in the source shell.
UPDATE:
To use export to set an environment variable, you can either use an existing variable:
A=10
# ...
export A
This ought to work in both bash and sh. bash also allows it to be combined like so:
export A=10
This also works...