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Detecting endianness programmatically in a C++ program
...e warned against by compiler. That's exactly what unions are for !
bool is_big_endian(void)
{
union {
uint32_t i;
char c[4];
} bint = {0x01020304};
return bint.c[0] == 1;
}
The principle is equivalent to the type case as suggested by others, but this is clearer - and...
How to set child process' environment variable in Makefile
...ever you can use make's export to force them to do so. Change:
test: NODE_ENV = test
to this:
test: export NODE_ENV = test
(assuming you have a sufficiently modern version of GNU make >= 3.77 ).
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Create a menu Bar in WPF?
...nel>
<Menu DockPanel.Dock="Top">
<MenuItem Header="_File">
<MenuItem Header="_Open"/>
<MenuItem Header="_Close"/>
<MenuItem Header="_Save"/>
</MenuItem>
</Menu>
<StackPanel></StackPa...
Run a callback only if an attribute has changed in Rails
...
Rails 5.1+
class Page < ActiveRecord::Base
before_save :do_something, if: :will_save_change_to_status_id?
private
def do_something
# ...
end
end
The commit that changed ActiveRecord::Dirty is here: https://github.com/rails/rails/commit/16ae3db5a5c6a08383b974ae...
How do I expire a PHP session after 30 minutes?
...a session timeout of your own. Both options mentioned by others (session.gc_maxlifetime and session.cookie_lifetime) are not reliable. I'll explain the reasons for that.
First:
session.gc_maxlifetime
session.gc_maxlifetime specifies the number of seconds after which data will be seen as 'garb...
Python Nose Import Error
...
You've got an __init__.py in your top level directory. That makes it a package. If you remove it, your nosetests should work.
If you don't remove it, you'll have to change your import to import dir.foo, where dir is the name of your dire...
What are the applications of binary trees?
...oving from one level to the next requires one comparison, and there are log_2(m) levels, for a total of log_2(m) comparisons.
In contrast, an n-ary tree will require log_2(n) comparisons (using a binary search) to move to the next level. Since there are log_n(m) total levels, the search will requi...
In C#, should I use string.Empty or String.Empty or “” to intitialize a string?
...1
.locals init ([0] string test1,
[1] string test11)
IL_0000: nop
IL_0001: ldsfld string [mscorlib]System.String::Empty
IL_0006: stloc.0
IL_0007: ldloc.0
IL_0008: stloc.1
IL_0009: ret
} // end of method Form1::Test1
.method private hidebysig instance void ...
How can I extract the folder path from file path in Python?
....path.split(os.path.abspath(existGDBPath))
('T:\\Data\\DBDesign', 'DBDesign_93_v141b.mdb')
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Can I have onScrollListener for a ScrollView?
...dited Sep 16 '16 at 6:48
Pavneet_Singh
33.3k55 gold badges3939 silver badges5757 bronze badges
answered Apr 29 '14 at 13:06
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