yarnom
f0b50d13ea
Add Go/Postgres admin APIs, Angular admin UI, manual build flow, asset uploads, markdown import/export, configurable slug generation, and the Yar reading theme. Exclude local docs and generated development artifacts from version control.
39 lines
1.4 KiB
Markdown
39 lines
1.4 KiB
Markdown
---
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id: cf7cfd71-d2ac-4f5a-a175-808ef410a339
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slug: linux-process-learning-2
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title: Linux 进程学习 二
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summary: ""
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status: published
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tags: []
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cover: ""
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version: 1
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slug_source: manual
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slug_locked: true
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published_at: "2022-10-16T16:13:33+08:00"
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created_at: "2022-10-16T16:13:33+08:00"
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updated_at: "2026-01-07T18:10:43+08:00"
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---
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## 创建进程
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在 Linux 中每个进程都是父进程创建的，Linux 启动时会创建init 进程，这是系统的第一个进程，其 PID 为 1。
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在 C 语言中，我们可以用fork函数创建新的进程：
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```c
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#include <unistd.h>
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pid_t fork(void);
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```
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- If fork() returns a negative value, the creation of a child process was unsuccessful.
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- fork() returns a zero to the newly created child process.
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- fork() returns a positive value, the process ID of the child process, to the parent. The returned process ID is of type pid_t defined in sys/types.h. Normally, the process ID is an integer. Moreover, a process can use function getpid() to retrieve the process ID assigned to this process.
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也就是：
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> On success, the PID of the child process is returned in the
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parent, and 0 is returned in the child. On failure, -1 is
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returned in the parent, no child process is created, and errno is
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set to indicate the error.
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也就是：
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- 返回负数，创建失败
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- 返回 0 ，就是子进程，它永远返回 0
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- 返回大于 0 的整数，这是父进程，它会返回子进程的pid
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## 终止进程
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