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java get file size efficiently
...m access is one of the major responsibilities of an OS. faqs.org/docs/linux_admin/buffer-cache.html To get good benchmarking results, the cache should be cleared before each run.
– z0r
Jul 6 '12 at 0:16
...
How do I get a PHP class constructor to call its parent's parent's constructor?
.../ main class that everything inherits
class Grandpa
{
public function __construct()
{
}
}
class Papa extends Grandpa
{
public function __construct($bypass = false)
{
// only perform actions inside if not bypassing
if (!$bypass) {
}
// call Gra...
What are the rules about using an underscore in a C++ identifier?
...r parameters. If you've come from an MFC background, you'll probably use m_foo . I've also seen myFoo occasionally.
5 An...
How are Python's Built In Dictionaries Implemented?
...keys' hashes. You can think of it like this:
hash key dict_0 dict_1 dict_2...
...010001 ffeb678c 633241c4 fffad420 ...
... ... ... ... ...
For a 64 bit machine, this could save up to 16 bytes per key per extra dictionary.
Shared Keys for...
How to check that an element is in a std::set?
...e in many STL containers such as std::map, std::set, ... is:
const bool is_in = container.find(element) != container.end();
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...
hasNext in Python iterators?
...icult to write an adaptor that stores the result of next() and provides has_next() and move_next().
– avakar
Dec 24 '12 at 21:10
6
...
How to get current CPU and RAM usage in Python?
...#!/usr/bin/env python
import psutil
# gives a single float value
psutil.cpu_percent()
# gives an object with many fields
psutil.virtual_memory()
# you can convert that object to a dictionary
dict(psutil.virtual_memory()._asdict())
# you can have the percentage of used RAM
psutil.virtual_memory().pe...
What is the meaning of “__attribute__((packed, aligned(4))) ”
...;
char Data4;
//1-byte Added here.
}sSampleStruct;
We can use __attribute__((packed, aligned(X))) to insist particular(X) sized padding. X should be powers of two. Refer here
typedef struct
{
char Data1;
int Data2;
unsigned short Data3;
char Data4;
}__attribute__((...
If isset $_POST
...
Since !empty() is already checks for both, you can use this:
if (!empty($_POST["mail"])) {
echo "Yes, mail is set";
} else {
echo "No, mail is not set";
}
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How to get number of entries in a Lua table?
...ole table with pairs(..).
function tablelength(T)
local count = 0
for _ in pairs(T) do count = count + 1 end
return count
end
Also, notice that the "#" operator's definition is a bit more complicated than that. Let me illustrate that by taking this table:
t = {1,2,3}
t[5] = 1
t[9] = 1
Ac...