Suppose I have a structure having fields name, age, salary and have passed address of age to a function fun( ).
How I can access the other member of the structure using the address of age?
Ans:
struct emp
{
char name[20] ;
int age ;
float salary ;
} ;
main( )
{
struct emp e ;
printf ( “\nEnter name: ” ) ;
scanf ( “%s”, e.name ) ;
printf ( “\nEnter age: ” ) ;
scanf ( “%d”, &e.age ) ;
printf ( “\nEnter salary: ” ) ;
scanf ( “%f”, &e.salary ) ;
fun ( &e.age ) ;
}
fun ( int *p )
{
struct emp *q ;
int offset ;
offset = ( char * ) ( & ( ( struct emp * ) 0 ) -> age ) – ( char * ) ( ( struct emp* ) 0 ) ;
q = ( struct emp * ) ( ( char * ) p – offset ) ;
printf ( “\nname: %s”, q -> name ) ;
printf ( “\nage: %d”, q -> age ) ;
printf ( “\nsalary: %f”, q -> salary ) ;
}
