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Change all files and folders permissions of a directory to 644/755
How would I change all files to 644 and all folders to 755 using chmod from the linux command prompt? (Terminal)
8 Answ...
How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
I've been digging through some parts of the Linux kernel, and found calls like this:
10 Answers
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Elastic Search: how to see the indexed data
...lore your ElasticSearch cluster is to use elasticsearch-head.
You can install it by doing:
cd elasticsearch/
./bin/plugin -install mobz/elasticsearch-head
Then (assuming ElasticSearch is already running on your local machine), open a browser window to:
http://localhost:9200/_plugin/head/
Alte...
How can I implement a tree in Python?
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I came across this answer via Google. This library is really nice. I especially love the ability to use the mixin class to make an tree of any object!
– Rÿck Nöthing
Mar 8 '19 at 1:21
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correct way to use super (argument passing)
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Shouldn't Base call super(Base, self).__init__()?
– cha0site
Jan 23 '12 at 14:47
4
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@property retain, assign, copy, nonatomic in Objective-C
...gners opted for the safer of the two solutions. In fact nonatomic is generally the better choice as it omits extremely expensive thread locks. The only reason to use atomic is if your property might be set from multiple threads (in which case omitting it can lead to an over-release or a leak).
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Reimport a module in python while interactive
... Redefinitions of names will override the old definitions, so this is generally not a problem, but if the new version of a module does not define a name that was defined by the old version, the old definition is not removed.
If a module imports objects from another module using from ... import ..., ...
What is a clean, pythonic way to have multiple constructors in Python?
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Actually None is much better for "magic" values:
class Cheese():
def __init__(self, num_holes = None):
if num_holes is None:
...
Now if you want complete freedom of adding more parameters:
class Cheese...
Weighted random numbers
...a weighted random numbers. I'm currently just banging my head against the wall and cannot figure this out.
7 Answers
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Odd behavior when Java converts int to byte?
...+ unsignedByte);
Would print out: "Signed: -1 Unsigned: 255"
What's actually happening here?
We are using bitwise AND to mask all of the extraneous sign bits (the 1's to the left of the least significant 8 bits.)
When an int is converted into a byte, Java chops-off the left-most 24 bits
111111...