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How to modify a global variable within a function in bash?
I'm working with this:
8 Answers
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Should operator
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The problem here is in your interpretation of the article you link.
Equality
This article is about somebody that is having problems correctly defining the bool relationship operators.
The operator:
Equality == and !=
Relationship < > <= >=
These operators should return a bool as ...
Why do we need a pure virtual destructor in C++?
...the real reason that pure virtual destructors are allowed is that to prohibit them would mean adding another rule to the language and there's no need for this rule since no ill-effects can come from allowing a pure virtual destructor.
Nope, plain old virtual is enough.
If you create an object wit...
Compare two MySQL databases [closed]
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If you're working with small databases I've found running mysqldump on both databases with the --skip-comments and --skip-extended-insert options to generate SQL scripts, then running diff on the SQL scripts works pretty well.
By skipping comm...
How does PHP 'foreach' actually work?
...e prefix this by saying that I know what foreach is, does and how to use it. This question concerns how it works under the bonnet, and I don't want any answers along the lines of "this is how you loop an array with foreach ".
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Android: Storing username and password?
...sword to be used inside an Android application, what is the best way to do it? Is it through the preferences screen (but what if the user misses this?), or pop up a dialog box and ask the user for the credentials? If so, I do have to maintain state for the application. How would I do this?
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How to create a file with a given size in Linux?
...purposes I have to generate a file of a certain size (to test an upload limit).
13 Answers
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Is it good practice to use the xor operator for boolean checks? [closed]
I personally like the exclusive or , ^ , operator when it makes sense in the context of boolean checks because of its conciseness. I much prefer to write
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What's the u prefix in a Python string?
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You're right, see 3.1.3. Unicode Strings.
It's been the syntax since Python 2.0.
Python 3 made them redundant, as the default string type is Unicode. Versions 3.0 through 3.2 removed them, but they were re-added in 3.3+ for compatibility with Python 2 to aide the 2...
When to use MongoDB or other document oriented database systems? [closed]
...latform for video- and audio-clips, photos and vector-grafics. We started with MySQL as the database backend and recently included MongoDB for storing all meta-information of the files, because MongoDB better fits the requirements. For example: photos may have Exif information, videos may have a...