What is the execution order in C language?

The order in which C language is executed in the computer can be divided into: 1. Editing; 2. Preprocessing; 3. Compilation; 4. Linking; 5. Execution.

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C language in Execution sequence in the computer:

• Editing: The process of writing code through the keyboard is editing

• Preprocessing: Include header files process (this function is only for the include instruction)

• Compile: including compilation and assembly

• Link: assemble The resulting file is converted into an executable file

The following article will introduce the specific content of each part to you

Edit

The process of editing refers to the process of writing programs and codes.

Preprocessing

Preprocessing is a process. In C language, preprocessing and Header files are used together

#include<stdio.h>

The # mark in the above statement is a preprocessing instruction, and include is a specific instruction in the preprocessing instruction, which contains the preprocessing function of a source file. is a header file that includes the file into the C language you want to write. This is a preprocessing directive. Of course, preprocessing is not just about files that contain this function, but also macro definition, conditional compilation, line control, diagnosis and other functions. This is specifically achieved through "#" "preprocessing instructions".

Compilation

Compilation includes assembly and compilation. Let’s look at the assembly process first.

The following diagram allows you to understand the process of forming assembly language from the source program:

The next step is the compilation process.

Compilation is the process of translating assembly language code into machine instruction code. The final result is the target file. The object file stores the machine language code of the source program.

Link

The target file must ultimately be linked to form an executable file before it can be executed.

Link means that a function in a source file may refer to a variable in another source file; then the link connects several related programs together, making all target files become one The entirety loaded and executed by the operating system.

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