大约有 44,665 项符合查询结果（耗时：0.0402秒） [XML]
What's the difference between Perl's backticks, system, and exec?
...
exec
executes a command and never returns.
It's like a return statement in a function.
If the command is not found exec returns false.
It never returns true, because if the command is found it never returns at all.
There is also no point in returning STDOUT, STDE...
What exactly is Arel in Rails 3.0?
I understand that it is a replacement for ActiveRecord and that it uses objects instead of queries.
4 Answers
...
Tactics for using PHP in a high-load site
...loads. Treat me as (sigh) an alien that has just landed on the planet, albeit one that knows PHP and a few optimisation techniques.
...
std::wstring VS std::string
..._t.
char vs. wchar_t
char is supposed to hold a character, usually an 8-bit character.
wchar_t is supposed to hold a wide character, and then, things get tricky:
On Linux, a wchar_t is 4 bytes, while on Windows, it's 2 bytes.
What about Unicode, then?
The problem is that neither char nor wchar_t...
Position a CSS background image x pixels from the right?
I think the answer is no, but can you position a background image with CSS, so that it is a fixed amount of pixels away from the right?
...
How can I make an svg scale with its parent container?
...g element's contents scale when size is non-native. Of course I could have it as a separate file and scale it like that.
7 ...
Is the size of C “int” 2 bytes or 4 bytes?
...Integer variable in C occupy 2 bytes or 4 bytes? What are the factors that it depends on?
13 Answers
...
Limitations of Intel Assembly Syntax Compared to AT&T [closed]
... Intel syntax, will I miss anything? Is there any reason I would want to switch to AT&T (outside of being able to read others' AT&T assembly)? My first clue is that gdb uses AT&T by default.
...
How do C++ class members get initialized if I don't do it explicitly?
Suppose I have a class with private memebers ptr , name , pname , rname , crname and age . What happens if I don't initialize them myself? Here is an example:
...
Why should casting be avoided? [closed]
...oid casting types as much as possible since I am under the impression that it's poor coding practice and may incur a performance penalty.
...