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When should the volatile keyword be used in C#?
...od explanation of the volatile keyword in C#? Which problems does it solve and which it doesn't? In which cases will it save me the use of locking?
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How can I increment a char?
I'm new to Python, coming from Java and C. How can I increment a char? In Java or C, chars and ints are practically interchangeable, and in certain loops, it's very useful to me to be able to do increment chars, and index arrays by chars.
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check if directory exists and delete in one command unix
Is it possible to check if a directory exists and delete if it does,in Unix using a single command? I have situation where I use ANT 'sshexec' task where I can run only a single command in the remote machine. And I need to check if directory exists and delete it...
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What is the minimum I have to do to create an RPM file?
...with only a couple of dependencies. It has a config file, /etc/foobar.conf and should be installed in /usr/bin/foobar.
9 A...
multiprocessing: sharing a large read-only object between processes?
...ng share objects created earlier in the program?"
No (python before 3.8), and Yes in 3.8 (https://docs.python.org/3/library/multiprocessing.shared_memory.html#module-multiprocessing.shared_memory)
Processes have independent memory space.
Solution 1
To make best use of a large structure with lots...
must appear in the GROUP BY clause or be used in an aggregate function
...
To workaround this issue, you must calculate the aggregate in a sub-query and then join it with itself to get the additional columns you'd need to show:
SELECT m.cname, m.wmname, t.mx
FROM (
SELECT cname, MAX(avg) AS mx
FROM makerar
GROUP BY cname
) t JOIN makerar m ON m.cname = t....
How to move Jenkins from one PC to another
...el comfortable with Jenkins as my long term "partner" in the build process and would like to "move" this Jenkins to a dedicated server.
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How to handle exceptions in a list comprehensions?
...amp;c in case of exceptions), so it's impossible, literally speaking, to "handle exceptions in a list comprehension" because a list comprehension is an expression containing other expression, nothing more (i.e., no statements, and only statements can catch/ignore/handle exceptions).
Function calls ...
How to change the name of a Django app?
... have changed the name of an app in Django by renaming its folder, imports and all its references (templates/indexes). But now I get this error when I try to run python manage.py runserver
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Hidden Features of Java
...e per-thread state.
Since JDK 1.5 Java has had extremely well implemented and robust concurrency tools beyond just locks, they live in java.util.concurrent and a specifically interesting example is the java.util.concurrent.atomic subpackage that contains thread-safe primitives that implement the co...