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Check if an apt-get package is installed and then install it if it's not on Linux
I'm working on a Ubuntu system and currently this is what I'm doing:
22 Answers
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Why does intellisense and code suggestion stop working when Visual Studio is open?
...crosoft Visual Studio 2012 . I will be working in a project, editing code and whatnot (after a period of time, anywhere from 5 minutes to over an hour) and all of a sudden, no more code suggestions or intellisense. Both seem to stop working completely at the same time.
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Two way sync with rsync
I have a folder a/ and a remote folder A/.
I now run something like this on a Makefile:
10 Answers
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How does the String class override the + operator?
...x = "+x;
The compiler converts "x = "+x; into a StringBuilder internally and uses .append(int) to "add" the integer to the string.
5.1.11. String Conversion
Any type may be converted to type String by string conversion.
A value x of primitive type T is first converted to a reference val...
Thread context switch Vs. process context switch
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The main distinction between a thread switch and a process switch is that during a thread switch, the virtual memory space remains the same, while it does not during a process switch.
Both types involve handing control over to the operating system kernel to perform the ...
What's a concise way to check that environment variables are set in a Unix shell script?
...(an empty string) is OK — not exactly what you want, but the alternative and older notation.
The second variant (using :?) requires DEST to be set and non-empty.
If you supply no message, the shell provides a default message.
The ${var?} construct is portable back to Version 7 UNIX and the Bourne ...
SQL query return data from multiple tables
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Part 1 - Joins and Unions
This answer covers:
Part 1
Joining two or more tables using an inner join (See the wikipedia entry for additional info)
How to use a union query
Left and Right Outer Joins (this stackOverflow answer is excelle...
Using Version Control for Home Development?
Up till now I have been developing my personal and school
projects at home without using any form of revision control
software to handle my changes and whatnot.
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Good Java graph algorithm library? [closed]
...eriences with any Java libraries for Graph algorithms. I've tried JGraph and found it ok, and there are a lot of different ones in google. Are there any that people are actually using successfully in production code or would recommend?
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The identity used to sign the executable is no longer valid
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It works for me as well. command + Q to exit XCode and restart. Cheers!
– Joey
Aug 30 '13 at 4:38
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