#include <stdlib.h>

unsigned int *pfun ( unsigned int *pa );

unsigned int Gdata = 0;

int main ( void )
{
  unsigned int  data;
  unsigned int *result = NULL;

  result = pfun ( &data );

  return ( 0 );
}

unsigned int *pfun ( unsigned int *pa )
{
  *pa   =  10;
  Gdata = *pa;

  return &Gdata;  //遵循1
}