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nil detection in Go
...ion method. Example:
type Config struct {
Host string
Port float64
setup bool
}
func NewConfig(host string, port float64) *Config {
return &Config{host, port, true}
}
func (c *Config) Initialized() bool { return c != nil && c.setup }
...
How to get unique device hardware id in Android? [duplicate]
...droid device ID?
More specifically, Settings.Secure.ANDROID_ID. This is a 64-bit quantity that is generated and stored when the device first boots. It is reset when the device is wiped.
ANDROID_ID seems a good choice for a unique device identifier. There are downsides: First, it is not 100% reliab...
How do you run a Python script as a service in Windows?
...just for this purpose) and no "installation" is needed. The zip contains a 64-bit and a 32-bit version of the utility. Either should work well on current systems (you can use the 32-bit version to manage services on 64-bit systems).
GUI approach
1 - install the python program as a service. Open a Wi...
Round a Floating Point Number Down to the Nearest Integer?
...s because 1.9999999999999999 is actually equal to 2.0 in the internal float64 representation. I. e. it's already rounded as soon as it is parsed into a float, as a 64 bit float cannot represent that many significant digits. You can verify that with evaluating 1.9999999999999999 == 2.0. And if you su...
What is the purpose of the “final” keyword in C++11 for functions?
... key disadvantage of vtables is that for any such virtual object (assuming 64-bits on a typical Intel CPU) the pointer alone eats up 25% (8 of 64 bytes) of a cache line. In the kind of applications I enjoy to write, this hurts very badly. (And from my experience it is the #1 argument against C++ fro...
Canvas width and height in HTML5
... zett42
10.5k33 gold badges1212 silver badges4646 bronze badges
answered Feb 8 '11 at 22:06
PhrogzPhrogz
261k9494 gold badge...
MongoDB数据导出导入工具：mongoexport,mongoimport - 大数据 & AI - 清泛...
..."age" : 24, "name" : "shane" }
证明数据导入成功
上面演示的是导入JSON格式的文件中的内容，如果要导入CSV格式文件中的内容，则需要通过--type参数指定导入格式，具体如下所示：
先删除数据
> db.students.remove()
> db.students.find()
...
USB Debugging option greyed out
...ebug when linked to the computer. Check it.
– DSlomer64
Jul 22 '16 at 12:25
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show 7 more comments
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Tool for comparing 2 binary files in Windows [closed]
...
mgutt
4,39922 gold badges4040 silver badges6464 bronze badges
answered Nov 17 '11 at 12:00
PolynomialPolynomial
24.7k66 g...
Where are static variables stored in C and C++?
...touched that, consider reading this post first.
Let's analyze a Linux x86-64 ELF example to see it ourselves:
#include <stdio.h>
int f() {
static int i = 1;
i++;
return i;
}
int main() {
printf("%d\n", f());
printf("%d\n", f());
return 0;
}
Compile with:
gcc -ggd...