大约有 40,000 项符合查询结果（耗时：0.0491秒） [XML]
What is the difference between user and kernel modes in operating systems?
... CPU instruction and
reference any memory address. Kernel
mode is generally reserved for the
lowest-level, most trusted functions
of the operating system. Crashes in
kernel mode are catastrophic; they
will halt the entire PC.
User Mode
In User mode, the executing code has no abili...
Why is printing to stdout so slow? Can it be sped up?
...ing I decided to look into it and was quite surprised to find that almost all the time spent is waiting for the terminal to process the results.
...
How can I pad an int with leading zeros when using cout
...ormatted output to a string (char* or char[]) not to console directly. Actually I am writing a function that returns formatted string
– shashwat
Dec 23 '12 at 9:32
14
...
Use of #pragma in C
...take some action, override some default, etc. that may or may not apply to all machines and operating systems.
See msdn for more info.
share
|
improve this answer
|
follow
...
When to use ' (or quote) in Lisp?
...al operator (quote) (or equivalent ' ) function does, yet this has been all over Lisp code that I've seen.
10 Answers
...
Remove all occurrences of char from string
...argument is regular expression, sometimes it won't work as expected, especially if this string comes from user input.
– vbezhenar
Jul 4 '12 at 8:50
9
...
Why is extending native objects a bad practice?
...ody does it "the wrong way", and adds enumerable types to Object , practically destroying all loops on any object?
8 Answe...
Unmangling the result of std::type_info::name
... calling function. This should be relatively easy, standard C++ has a type_info class. This contains the name of the typeid'd class/function/etc. but it's mangled. It's not very useful. I.e. typeid(std::vector<int>).name() returns St6vectorIiSaIiEE .
...
pandas GroupBy columns with NaN (missing) values
...n the Missing Data section of the docs:
NA groups in GroupBy are automatically excluded. This behavior is consistent with R, for example.
One workaround is to use a placeholder before doing the groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fil...
What exactly does an #if 0 … #endif block do?
...entire thing. And the #if 0s will nest with each other, like so:
#if 0
pre_foo();
#if 0
foo();
bar(x, y); /* x must not be NULL */
baz();
#endif
quux();
#endif
Although of course this can get a bit confusing and become a maintenance headache if not commented properly.
...