Linux系统调用--getpid/getppid函数详解

【getpid/getppid系统调用】   
    
功能描述： 
getpid返回当前进程标识，getppid返回父进程标识。

  
用法：  
#include <sys/types.h>
#include <unistd.h>

pid_t getpid(void);
pid_t getppid(void);

例子：

1. #include <stdlib.h>

2. #include <stdio.h>

3. #include <sys/types.h>

4.  

5. int main(void)

6. {

7. pid_t pid;

8. printf("Before fork ...\n");

9.  

10. switch(pid = fork()) {

11. case -1:

12. printf("Fock call fail\n");

13. exit(1);

14.  

15. case 0:

16. printf("The pid of child is: %d\n", getpid());

17. printf("The pid of child's parent is: %d\n", getppid());

18. printf("Child exiting...\n");

19. exit(0);

20.  

21. default:

22. printf("The pid of parent is: %d\n", getpid());

23. printf("the pid of parent's child is: %d\n", pid);

24. }

25.  

26. printf("After fork, program exiting...\n");

27. exit(0);

28. }

29.  

getpid() getppid()进程和父进程函数

getpid()和getppid()进程和父进程函数，在调用中都不能返回错误，下面的程序输出了他的进程ID和父进程ID，由于不能保证pid_t 能够放进 int类型中去，返回值被转为long 整型输出

1. main()

2.  

3. {

4.  

5. #include <stdio.h>

6.  

7. #include <unistd.h>

8.  

9. printf ("I am process %ld",(long)getpid());

10.  

11. printf ("My parent is %ld",(long)getppid());

12.  

13. return(0);

14.  

15. }

标签：getppid,Linux,pid,getpid,printf,进程,include
来源： https://blog.csdn.net/ll148305879/article/details/90751800