大约有 14,000 项符合查询结果（耗时：0.0224秒） [XML]
What is the difference between user and kernel modes in operating systems?
...ttp://wiki.osdev.org/Global_Descriptor_Table
the segment registers CS, DS, etc., which point to the index of an entry in the GDT.
For example, CS = 0 means the first entry of the GDT is currently active for the executing code.
What can each ring do?
The CPU chip is physically built so that:
...
What is the difference between the kernel space and the user space?
...r processes have to use the predefined system calls i.e. open, read, write etc. Also, the C library functions like printf call the system call write in turn.
The system calls act as an interface between the user processes and the kernel processes. The access rights are placed on the kernel space i...
How to capture no file for fs.readFileSync()?
...tead pass the error in the callback and handle it there: fs.readFile('/etc/passwd', (err, data) => { if (err) throw err; console.log(data); }); from: nodejs.org/dist/latest-v12.x/docs/api/…
– K.H. B
Mar 30 at 16:44
...
Having Django serve downloadable files
...t the user can potentially download any file (ie. what if you pass "f=/etc/passwd" ?) There are a lot of things that help prevent this (user permissions, etc), but just be aware of this obvious but common security risk. It's basically just a subset of validating input: If you pass in a filename to...
Is PHP compiled or interpreted?
... performance penalty as PHP recompiles my source code for every request?", etc.)
share
|
improve this answer
|
follow
|
...
How do cache lines work?
... a rule of thumb, if the processor can't forecast a memory access (and prefetch it), the retrieval process can take ~90 nanoseconds, or ~250 clock cycles (from the CPU knowing the address to the CPU receiving data).
By contrast, a hit in L1 cache has a load-use latency of 3 or 4 cycles, and a store...
Memcached下一站：HandlerSocket！ - 更多技术 - 清泛网 - 专注C/C++及内核技术
...形中让Memcached成为故障的根源：
Memcached数据一致性的问题：当MySQL数据变化后，如果不能及时有效的清理掉过期的数据，就会造成数据不一致。这在强调即时性的Web2.0时代，不可取。
Memcached崩溃后的雪崩效应：作为缓存的Memc...
How to determine whether a given Linux is 32 bit or 64 bit?
...et your specific machine hardware name run
uname -m
You can also call
getconf LONG_BIT
which returns either 32 or 64
share
|
improve this answer
|
follow
...
Why use sprintf function in PHP?
...NTO `Users` SET `user`='%s',`password`='%s',`realname`='%s';", $username, $passwd_hash, $realname);
This method does of course have other uses, such as when printing output as HTML, etc.
Edit: For security reasons, when using a technique as above you must sanitise all input variables with mysql_r...
What does $$ mean in the shell?
... as root and I create /tmp/yourprogname13395 as a symlink pointing to /etc/passwd -- and you write into it.
This is a bad thing to be doing in a shell script. If you're going to use a temporary file for something, you ought to be using a better language which will at least let you add the "exclusiv...