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What is a daemon thread in Java?
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For posterity, setDamon(boolean) can only be called before the thread has been started. By default the thread inherits the daemon status of its parent thread.
– Gray
Nov 30 '11 at 13:47
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Increasing the maximum number of TCP/IP connections in Linux
...local_port_range = 32768 61000
net.ipv4.tcp_fin_timeout = 60
This basically means your system cannot consistently guarantee more than (61000 - 32768) / 60 = 470 sockets per second. If you are not happy with that, you could begin with increasing the port_range. Setting the range to 15000 61000 is...
Calculate distance between 2 GPS coordinates
...y solution:
#include <math.h>
#include "haversine.h"
#define d2r (M_PI / 180.0)
//calculate haversine distance for linear distance
double haversine_km(double lat1, double long1, double lat2, double long2)
{
double dlong = (long2 - long1) * d2r;
double dlat = (lat2 - lat1) * d2r;
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Should I pass a shared_ptr by reference? [duplicate]
...mber of bugs arise from improper lifetime management. What's worse conceptually is that it is never clear who owns the objects whose pointers the container stores. The pointers could even be a mix of pointers to dynamic objects, automatic objects, and garbage. Nobody can tell. So the standard soluti...
Why is the order in dictionaries and sets arbitrary?
...der:
>>> {'bar': None, 'foo': None}
{'foo': None, 'bar': None}
All slots except 3 and 4 are empty, looping over the table first lists slot 3, then slot 4, so 'foo' is listed before 'bar'.
bar and baz, however, have hash values that are exactly 8 apart and thus map to the exact same slot...
Purpose of returning by const value? [duplicate]
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In the hypothetical situation where you could perform a potentially expensive non-const operation on an object, returning by const-value prevents you from accidentally calling this operation on a temporary. Imagine that + returned a non-const value, and you could write:
(a + b).expensiv...
Rails auto-assigning id that already exists
...y OP edit
– D-Nice
Jun 17 '12 at 21:32
I don't understand why this happened to begin with? This has happened to me and...
How to serialize a lambda?
...le)() -> System.out.println("Serializable!");
And the lambda automagically becomes serializable.
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Regular expression: find spaces (tabs/space) but not newlines
... You'll need to either normalize your strings first (such as by replacing all \u3000 with \u0020), or you'll have to use a character set that includes this codepoint in addition to whatever other whitespace you're targeting, such as [ \t\u3000].
If you're using Perl or PCRE, you have the option of...
Why does the C++ STL not provide any “tree” containers?
...we have
std::map (and std::multimap)
std::set (and std::multiset)
Basically the characteristics of these two containers is such that they practically have to be implemented using trees (though this is not actually a requirement).
See also this question:
C tree Implementation
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