Prog#223: load entire file into an array & display it

/*
load entire file into an array & display it 
Program#223
*/
#include<stdio.h>
main(int argc,char *argv[])
{
int p,i,j;
char a[200];
if(argc!=2)
{
printf("error: no.of arg");
return 0;
}
p=open(argv[1], 0);
if(p==-1)
{
printf("file open error");
return 0;
}
j=0;
i=read(p,&a[j],1);
while(i>0)
{
j++;
i=read(p,&a[j],1);
}
a[j]='\0';
printf("%s", a)
close(p);
}