how to use define

This article will explain in detail the use of a very broad mem_root structure in MySQL, while eliminating the debug section of the information, only to analyze the normal situation, the use of mem_root in MySQL to do the memory allocation

enable built-in Message QueuingPlace the Os_cfg_task_q_en 1 API Functions #if os_cfg_task_q_en > 0u //delete os_msg_qty Ostaskqflush (OS_TCB *P_TCB, os_err *p_err); Wait -1 void *ostaskqpend (os_tick timeout,

The Linux kernel manages the process through a struct called the process descriptor task_struct , which contains all the information required for a process. It is defined in the include/linux/sched.h file.When it comes to task_struct structs, it can

This technique comes from my actual development:Inet_addr This function is used to turn the IP address into a network byte order, his prototype: in_addr_t inet_addr (const char *CP);The return value is a in_addr_t type, it is clear that this is not

errno defined in , the error Exx macro is defined in the Errno-base.h and errno.h under the/usr/include/asm-generic folder, respectively, defining the 1-34, 35-132 error definitions.The strerror () function returns an error description string based

1. Define (that is, host variable)The main role of the host variable is to act as an alternative variable, a medium in which the host environment can interact with Oracle . When you define a host variable by define, you must specify the variable

C + + can use the const to define constants, or define constants using define #, which has more advantages than the latter.1) const data constants have data types, and macro constants do not have data types. The compiler can perform type safety

In PowerShell, we can customize a function to implement a specific function to achieve the purpose of reuse. Prepare to share it with a small series from simple to complex.First, we write a very simple custom function.Goal:After entering the name

ReviewIn the previous article, we introduced the Linux driver debugging method, which describes the concurrency and the state of the drive programming and how to handle concurrency and contention. First, what is concurrency and normality?

ReviewIn the previous article, we introduced the Linux driver debugging method, which describes the concurrency and the state of the drive programming and how to handle concurrency and contention.First, what is concurrency and normality? concurrency

This is I saw a piece about Requirejs beginner's article, writes well, below unifies own understanding to record:Original: http://www.sitepoint.com/understanding-requirejs-for-effective-javascript-module-loading/Modular programming is used to break

NAMEStat Get file propertiesThis function is located in the header fileFunction Prototypes:int stat (const char *path, struct stat *buf);Parameters:Path file paths + file nameBUF Pointer to bufferreturn value:-1 encountered an error0 successful

The C + + language can use const to define constants, or you can use #define来定义常量. But the former has more advantages than the latter: Const constants have data types, and macro constants do not have data types. The compiler can perform

Interrupt1. Indicator Range 1.1 Interrupt rateShould be combined with CPU utilization analysis, if CPU utilization is reasonable, a large number of interrupts are acceptable. A large interrupt value, accompanied by a slow performance of the system,

What is a lambda? Lambda expression is an anonymous function, and lambda expression is named after the lambda calculus in mathematics, directly corresponding to it (lambda abstraction), an anonymous function, That is, a function without a

1 /*2 * stdinredir2.c3 * shows, methods for redirecting , standard input4 * Use #define to set one or the other5 */6#include 7#include 8 /*#define Close_dup/*open, close, DUP, close*/9 /*#define USE_DUP2/*opne, dup2, close*/Ten intMainvoid) { One

PHP is a weak type of language PHP has 8 types of Chinese4 scalar//Only one value can be stored1. Integral type: int integer2. Boolean: BOOL Boolean3. Floating-point type: float,double,real4. Character type: string2 compound types//A variable can

This article mainly introduces the view function application of Angularjs, including Ng-view and Ng-template, and the use of $routeprovider, and $routeProvider need friends can refer to the following ANGULARJS supports the application of a single

In C + +, in order to solve some frequently called small function large consumption stack space or is called stack memory problem, especially the introduction of the inline modifier, expressed as an inline function. Probably speaking here, many

Show some days ago some netizens asked: the ASP recordset output into N columns of the form display method, now write a, convenient for everyone to use. ' Define variable Dim Cn,rs,sql Sql = "Select CustomerID from Orders" ' Total Records