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Is there a way to check if a file is in use?
... will try to access the file before it's been saved back to the filesystem and throw an error: "File in use by another process" .
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Why do we need virtual functions in C++?
I'm learning C++ and I'm just getting into virtual functions.
26 Answers
26
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Passing command line arguments to R CMD BATCH
.... I am now at the point where I would like to pass an argument to the command, but am having some issues getting it working. If I do R CMD BATCH my_script.R blabla then blabla becomes the output file, rather than being interpreted as an argument available to the R script being executed.
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What is a “static” function in C?
...minology never uses the word "method"; that's Java terminology -- in C++ standard documents it is always called "member function" (see this answer or this glossary of C++ vs Java terms (e.g. C++ uses "data member" and Java uses "field", etc)).
– ShreevatsaR
Jan...
How can I measure the similarity between two images? [closed]
...images with a text added vs. another without
mirrored images
The easiest and simplest algorithm I've seen for this is just to do the following steps to each image:
scale to something small, like 64x64 or 32x32, disregard aspect ratio, use a combining scaling algorithm instead of nearest pixel
sc...
Suppressing “is never used” and “is never assigned to” warnings in C#
...g restore 0169
To suppress warnings for "Field XYZ is never assigned to, and will always have its default value XX", you do this:
#pragma warning disable 0649
... field declaration
#pragma warning restore 0649
To find such warning numbers yourself (ie. how did I know to use 0169 and 0649), you ...
Why is typeof null “object”?
I'm reading 'Professional Javascript for Web Developers' Chapter 4 and it tells me that the five types of primitives are: undefined, null, boolean, number and string.
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What are -moz- and -webkit-? [duplicate]
I am a beginner at CSS and when I was looking at some CSS code the other day, I found these lines. In the tutorials I used to learn CSS, I have never seen anything like these lines. Could someone please explain these lines to me or give me a source where I could learn to implement lines like these?
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JavaScript OR (||) variable assignment explanation
... variable is falsy.
The boolean operators in JavaScript can return an operand, and not always a boolean result as in other languages.
The Logical OR operator (||) returns the value of its second operand, if the first one is falsy, otherwise the value of the first operand is returned.
For example:...
How to make MySQL handle UTF-8 properly
...tion I asked yesterday suggested that I should make sure my database can handle UTF-8 characters correctly. How I can do this with MySQL?
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