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What is the difference between char s[] and char *s?
...to modify the contents of the array, the behavior is undefined.
GCC 4.8 x86-64 ELF implementation
Program:
#include <stdio.h>
int main(void) {
char *s = "abc";
printf("%s\n", s);
return 0;
}
Compile and decompile:
gcc -ggdb -std=c99 -c main.c
objdump -Sr main.o
Output con...
A fast method to round a double to a 32-bit int explained
...
This kind of "trick" comes from older x86 processors, using the 8087 intructions/interface for floating point. On these machines, there's an instruction for converting floating point to integer "fist", but it uses the current fp rounding mode. Unfortunately, the...
C# 'is' operator performance
...interesting to see that x64 created faster but executed as/is slower than x86
x64 Release Mode:
Stopwatch:
As: 561ms
Is: 597ms
Base property: 539ms
Base field: 555ms
Base RO field: 552ms
Virtual GetEnumType() test: 556ms
Virtual IsB() test: 588ms
Create Time : 10416ms
UtcNow:
As: 499ms...
Is there any advantage of using map over unordered_map in case of trivial keys?
... a time_hash_map program to time them. For example, with gcc 4.4.2 on an x86_64 Linux system
$ ./time_hash_map
TR1 UNORDERED_MAP (4 byte objects, 10000000 iterations):
map_grow 126.1 ns (27427396 hashes, 40000000 copies) 290.9 MB
map_predict/grow 67.4 ns (10000000 hashes, 400...
Start / Stop a Windows Service from a non-Administrator user account
...account to manage the BST
services.
(subinacl.exe is in C:\Program Files (x86)\Windows Resource Kits\Tools\).
cd C:\Program Files (x86)\Windows Resource Kits\Tools\
subinacl /SERVICE \\MachineName\bst /GRANT=domainname.com\username=F or
subinacl /SERVICE \\MachineName\bst /GRANT=username=F
Logout an...
.a: error adding symbols: File format not recognized 原因 - 操作系统(...
...也可能出现编译能通过，但ldd报链接失败不能运行。原因是：在低版本Linux GCC上编译工程 Linux编译链接时报错：xxx.a: error adding symbols: File format not recognized。也可能出现编译能通过，但ldd报链接失败不能运行。
原因是：在低版...
解决：apache2.service: Failed to run \'start\' task: No such file or d...
...ice: Failed to run & 39;start& 39; task: No such file or directory。原因是：& 39; var tmp& 39;目录被删掉了导致的。mkdir var tmp 搞定。今天 systemctl reload apache2.service 重启apache2时，出现一个错误：apache2.service: Failed to run 'start' task: No such file or direct...
Homebrew作者解不出面试题，被Google拒绝 - 创意 - 清泛网 - 专注C/C++及内核技术
Homebrew作者解不出面试题，被Google拒绝Homebrew是Mac上一套流行的软件包管理工具，可以通过命令行搜索、安装、卸载软件包。近日，其作者在进入Google的面试中，因解不出一个二叉 Homebrew是Mac上一套流行的软件包管理工具，可以...
【解决】iOS 14任务栏出现一块空白 - 创意 - 清泛网 - 专注C/C++及内核技术
...空白升级到iOS 14后，发现任务栏出现了一块空白，如图：是家庭中心显示的区域出现的空白，影响显示效果。可以去 设置 -> "控制中心"，将家庭控制显示关掉，这样就没有空白区域了： 升级到iOS 14后，发现任务栏出现了一块...
开心一刻 - 轻松一刻 - 清泛网 - 专注C/C++及内核技术
...切中当前经济热点。小明：我家小区 那一带，一路上 全是炒股的。“一带一路”
老师：请用“一带一路”造句，切中当前经济热点。
小明：我家小区 那一带，一路上 全是炒股的。
开心一刻