In Linux, related functions can be achieved by creating a subprocess and executing functions in the subprocess. This is achieved by using the "fork()" and "exec()" series of functions. The specific steps are as follows: 1. Use the "fork()" function to create a child process; 2. In the child process, use the "exec()" series of functions to execute specific functions.
The operating system of this tutorial: Linux5.18.14 system, Dell G3 computer.
In Linux, related functions can be achieved by creating a subprocess and executing functions in the subprocess. This can be achieved by using the fork() and exec() series of functions. The specific steps are as follows:
Use the fork() function to create a child process. fork() copies the code, data, and resources of the current process and creates a child process that is almost identical to the parent process. In the parent process, fork() returns the ID of the child process, while in the child process, fork() returns 0. By judging the return value of fork(), the program can distinguish the logical paths of the parent process and the child process.
In the child process, you can use the exec() series of functions to execute specific functions. For example, the execl() function can be used to execute a specified function in the child process.
The following is a simple example:
#include <stdio.h> #include <stdlib.h> #include <unistd.h> void child_function() { printf("This is the child process "); // 子进程执行的逻辑处理 } int main() { pid_t pid = fork(); if (pid < 0) { // 处理fork()错误的情况 fprintf(stderr, "Fork failed "); exit(1); } else if (pid == 0) { // 子进程 child_function(); exit(0); } else { // 父进程 printf("This is the parent process "); // 父进程执行的逻辑处理 // 等待子进程结束 wait(NULL); printf("Child process completed "); } return 0; }在上述示例中,通过fork()创建了一个子进程,在子进程中通过child_function()函数执行特定逻辑。父进程则可以执行自己的逻辑,并通过wait()等待子进程结束。
It should be noted that the exec() series of functions will replace the image of the current process and directly load the new executable file or function, will not return the location of the original function. Therefore, if you need to execute a specific function in the child process, you can use library functions or other methods to complete it.
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