Why getppid() from the child return 1
13,593
Because parent process is finished by the time the child asks for its parent's pid.
When a process finishes, all its children are reassigned as children of the init process, which pid is 1.
Try using wait()
in parent's code to wait for the child to execute. It should then work as you expect.
Related videos on Youtube
Author by
user567879
Updated on September 18, 2022Comments
-
user567879 over 1 year
I was running the program
#include<stdio.h> #include <unistd.h> main() { pid_t pid, ppid; printf("Hello World1\n"); pid=fork(); if(pid==0) { printf("I am the child\n"); printf("The PID of child is %d\n",getpid()); printf("The PID of parent of child is %d\n",getppid()); } else { printf("I am the parent\n"); printf("The PID of parent is %d\n",getpid()); printf("The PID of parent of parent is %d\n",getppid()); } }
THe output I got was.
$ ./a.out Hello World1 I am the parent The PID of parent is 3071 The PID of parent of parent is 2456 I am the child The PID of child is 3072 The PID of parent of child is 1
I couldnt understand the line
The PID of parent of child is 1
It should have been 3071?