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ERROR:'keytool' is not recognized as an internal or external command, operable program or batch file
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Check that the directory the keytool executable is in is on your %PATH% environment variable.
For example, on my Windows 7 machine, it is in
C:\Program Files (x86)\Java\jre6\bin, and my %PATH% variable looks like C:\Program Files (x86)\Common F...
How to do a logical OR operation in shell scripting
I am trying to do a simple condition check, but it doesn't seem to work.
8 Answers
8
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Difference between framework vs Library vs IDE vs API vs SDK vs Toolkits? [closed]
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An IDE is an integrated development environment - a suped-up text editor with additional support for developing (such as forms designers, resource editors, etc), compiling and debugging applications. e.g Eclipse, Visual Studio.
A Library is a chunk of code that you can call from your own code,...
Spinlock versus Semaphore
What are the basic differences between a semaphore & spin-lock?
11 Answers
11
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How do I choose a HTTP status code in REST API for “Not Ready Yet, Try Again Later”? [closed]
... time. There's a batch process in the server that generates all the blobs for all the thingies. Thingy 1234 already exists and its data, other than the blob, is already available. The server hasn't got to generating thingy 1234's blob yet.
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What are POD types in C++?
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POD stands for Plain Old Data - that is, a class (whether defined with the keyword struct or the keyword class) without constructors, destructors and virtual members functions. Wikipedia's article on POD goes into a bit more detail and d...
How can I determine if a variable is 'undefined' or 'null'?
How do I determine if variable is undefined or null ?
30 Answers
30
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When to wrap quotes around a shell variable?
Could someone tell me whether or not I should wrap quotes around variables in a shell script?
5 Answers
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What is the difference between
...rackets; not sent to client (as opposed to HTML comments).
Visit Ruby Doc for more infos about ERB.
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&& (AND) and || (OR) in IF statements
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No, it will not be evaluated. And this is very useful. For example, if you need to test whether a String is not null or empty, you can write:
if (str != null && !str.isEmpty()) {
doSomethingWith(str.charAt(0));
}
or, the other way around
if (str == null || str.isEmpt...