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Is “argv[0] = name-of-executable” an accepted standard or just a common convention?
...n, will argv[0] always be the name of the executable? Or is this just a common convention and not guaranteed to be true 100% of the time?
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What is the significance of load factor in HashMap?
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edited Jun 20 at 9:12
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answered Jun 5 '12 at 17:17
NPENPE
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What is the point of a private pure virtual function?
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The question in the topic suggest a pretty common confusion. The confusion is common enough, that C++ FAQ advocated against using private virtuals, for a long time, because confusion seemed to be a bad thing.
So to get rid of the confusion first: Yes, private virtual...
Why isn't sizeof for a struct equal to the sum of sizeof of each member?
... state that structure alignment is implementation-defined. Therefore each compiler may choose to align data differently, resulting in different and incompatible data layouts. For this reason, when dealing with libraries that will be used by different compilers, it is important to understand how th...
Solving a “communications link failure” with JDBC and MySQL [duplicate]
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I have had the same problem in two of my programs. My error was this:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
I spent ...
When do you use Java's @Override annotation and why?
...de a method for two benefits. Do it so that you can take advantage of the compiler checking to make sure you actually are overriding a method when you think you are. This way, if you make a common mistake of misspelling a method name or not correctly matching the parameters, you will be warned tha...
How to validate IP address in Python? [duplicate]
...at's the best way to validate that an IP entered by the user is valid? It comes in as a string.
11 Answers
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What requirement was the tuple designed to solve?
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When writing programs it is extremely common to want to logically group together a set of values which do not have sufficient commonality to justify making a class.
Many programming languages allow you to logically group together a set of otherwise unrelated v...
SqlException from Entity Framework - New transaction is not allowed because there are other threads
...ach (RivWorks.Model.NegotiationAutos.Client client in clientList)
{
var companyFeedDetailList = from a in _dbRiv.AutoNegotiationDetails where a.ClientID == client.ClientID select a;
// ...
}
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How can I check if a program exists from a Bash script?
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Answer
POSIX compatible:
command -v <the_command>
Example use:
if ! command -v COMMAND &> /dev/null
then
echo "COMMAND could not be found"
exit
fi
For Bash specific environments:
hash <the_command> # For regul...