wait ( Process System Call ) in C Program

 #include   <stdio.h>  

#include   <stdlib.h>

#include   <sys/types.h>  

#include   <sys/wait.h>

#include   <unistd.h>  

int  main()

{

int  i, status;

pid_t pid;

pid = fork();

if  (pid == -1) {

printf( "Process Creation Error. \n" );

exit(-1);

}

else   if  (pid > 0) {

wait( NULL );

printf( "Parent Starts: \n" );

printf( "Even Numbers: \n" );

for  (i = 0; i <= 10; i++) {

if  (!(i % 2)) {

printf( "%d \n" , i);

}

}

printf( "Parent Ends. \n" );

printf( "\n" );

}

else  {

printf( "Child Starts: \n" );

printf( "Odd Numbers: \n" );

for  (i = 0; i <= 10; i++) {

if  (i % 2) {

printf( "%d \n" , i);

}

}

printf( "Child Ends. \n" );

printf( "\n" );

}

return  0;

}