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Reference: What is variable scope, which variables are accessible from where and what are “undefined
What is "variable scope" in PHP? Are variables from one .php file accessible in another? Why do I sometimes get "undefined variable" errors?
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Difference between onStart() and onResume()
I can't get the meaning of onStart() transition state. The onResume() method is always called after onStart() . Why can't it be the onResume() is invoked after onRestart() and onCreate() methods just excluding onStart() ? What is its purpose?
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Can two applications listen to the same port?
Can two applications on the same machine bind to the same port and IP address? Taking it a step further, can one app listen to requests coming from a certain IP and the other to another remote IP?
I know I can have one application that starts off two threads (or forks) to have similar behavior, but...
What is a Python egg?
I'm new to Python and am just trying to understand how its packages work. Presumably "eggs" are some sort of packaging mechanism, but what would be a quick overview of what role they play and may be some information on why they're useful and how to create them?
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Bundler: Command not found
I am hosting on a vps, ubuntu 10.04, rails 3, ruby and mysql installed correctly by following some tutorials. If I run bundle check or bundle install I get the error '-bash: bundle: command not found'. From gem list --local I see 'bundler (1.0.2, 1.0.0)' is installed.
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How do browser cookie domains work?
Due to weird domain/subdomain cookie issues that I'm getting, I'd like to know how browsers handle cookies. If they do it in different ways, it would also be nice to know the differences.
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Will using 'var' affect performance?
...nly necessary for anonymous types, that it is used nonetheless to make writing code 'quicker'/easier and 'just because'.
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How to highlight and color gdb output during interactive debugging?
...I just prefer gdb as it is, but would like to see its output with some terminal colors.
11 Answers
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Scanner is skipping nextLine() after using next() or nextFoo()?
I am using the Scanner methods nextInt() and nextLine() for reading input.
19 Answers
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Are there any downsides to passing structs by value in C, rather than passing a pointer?
Are there any downsides to passing structs by value in C, rather than passing a pointer?
10 Answers
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