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How to change the session timeout in PHP?
...cted immediately but only whenever the session GC kicks in.
GC is a potentially expensive process, so typically the probability is rather small or even zero (a website getting huge numbers of hits will probably forgo probabilistic GC entirely and schedule it to happen in the background every X minut...
How do you query for “is not null” in Mongo?
...
This will return all documents with a key called "IMAGE URL", but they may still have a null value.
db.mycollection.find({"IMAGE URL":{$exists:true}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
d...
Multiple constructors in python? [duplicate]
... Now you can do:
c = C(fd)
# or:
c = C.fromfilename('a filename')
Notice all those classmethods still go through the same __init__, but using classmethods can be much more convenient than having to remember what combinations of keyword arguments to __init__ work.
isinstance is best avoided becaus...
How to use timeit module
...
The way timeit works is to run setup code once and then make repeated calls to a series of statements. So, if you want to test sorting, some care is required so that one pass at an in-place sort doesn't affect the next pass with already sorted data (that, of course, would make the Timsort reall...
What is the difference between ManualResetEvent and AutoResetEvent in .NET?
...or. The ManualResetEvent is the door, which needs to be closed (reset) manually. The AutoResetEvent is a tollbooth, allowing one car to go by and automatically closing before the next one can get through.
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Use cases for the 'setdefault' dict method
...e case: Grouping items (in unsorted data, else use itertools.groupby)
# really verbose
new = {}
for (key, value) in data:
if key in new:
new[key].append( value )
else:
new[key] = [value]
# easy with setdefault
new = {}
for (key, value) in data:
group = new.setdefault(k...
How to change Rails 3 server default port in develoment?
...
First - do not edit anything in your gem path! It will influence all projects, and you will have a lot problems later...
In your project edit script/rails this way:
#!/usr/bin/env ruby
# This command will automatically be run when you run "rails" with Rails 3 gems installed from the root...
Problems with lib-icu dependency when installing Symfony 2.3.x via Composer
I've had no problems installing Symfony 2.2.x using Composer, I've always just copied the stable version at http://symfony.com/download .
...
What is the meaning of “__attribute__((packed, aligned(4))) ”
...gned(1))) sSampleStruct;
so the above specified gcc attribute does not allow the structure padding. so the size will be 8 bytes.
If you wish to do the same for all the structures, simply we can push the alignment value to stack using #pragma
#pragma pack(push, 1)
//Structure 1
......
//Stru...
undefined reference to boost::system::system_category() when compiling
...raries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
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