Fork in Operating System, Lecture notes of Operating Systems

Download Fork in Operating System and more Lecture notes Operating Systems in PDF only on Docsity!

Operating Systems

CSM 604: Lecture 7

Process Management

Process

Memory Layout  (^) Text Section – executable code  (^) Data Section – global variables  (^) Stack – function parameters, return addresses and local variables.  (^) Heap – dynamically allocated during runtime  (^) Current Activity

Process Creation

Principal events that cause process creation

1. System initialization
2. Execution of a process creation system
3. User request to create a new process
4. Initiation of a batch job

fork()

fork()

main() { pid_t pid; pid = fork(); if (pid == 0) printf("\nI am the child %d\n",pid); else printf("\nI am the parent %d\n",pid); }

fork()

fork()

Process Creation

exec

int main(void) { int i; int status; pid_t pid; if(fork()) { pid = wait(&status); } else { execlp("date","date",0); } return 0; }

To be continued…

Questions?