Prog#206: read from file & display it on screen

/*
read from file & display it on screen
Program#206
*/
#include<stdio.h>
main(int argc,char *argv[])
{
union xyz{
struct bio{
char name [25];
int age;
float salary;
char addr [20];
}a;
char b[sizeof(struct bio)];
};
union xyz m;
FILE *fp;
int i;
if(argc!=2)
{
printf("error. no.of arg");
return 0;
}
fp=fopen (argv[1], "r");
if(fp==NULL)
{
printf("file open error");
return 0;
}
for(i=0;i<sizeof(struct bio);i++)
m.b[i]=getc(fp);
printf("%s %d %f %s", m.a.name, m.a.age, m.a.salary, m.a.addr);
fclose(fp);
}