Programming

struct __FILE_TAG       /* needs to be binary-compatible with old versions */
{
#ifdef _STDIO_REVERSE
        unsigned char   *_ptr;  /* next character from/to here in buffer */
        ssize_t         _cnt;   /* number of available characters in buffer */
#else
        ssize_t         _cnt;   /* number of available characters in buffer */
        unsigned char   *_ptr;  /* next character from/to here in buffer */
#endif
        unsigned char   *_base; /* the buffer */
        unsigned char   _flag;  /* the state of the stream */
        unsigned char   _file;  /* UNIX System file descriptor */
        unsigned        __orientation:2; /* the orientation of the stream */
        unsigned        __ionolock:1;   /* turn off implicit locking */
        unsigned        __seekable:1;   /* is file seekable? */
        unsigned        __filler:4;
};

#include<stdio.h>
#include<string.h>

int main()
{
int *i, j;
size_t n;
const char *buf;
unsigned char *t;
FILE *fp;

fp = fopen("test.txt", "r+" );

buf = "This is Test String , This is Test String\n" ;

//j = strlen(buf);
//j = strlen(fp->_p);

n = fwrite(buf, 1, 10, fp);

if( fp->_p )
        printf(" Its not null");

//i = (int *)memcpy((void *)t, (const void *)buf, (size_t)(10)) ;

j = (int)fp->_r ;
t = fp->_p ;
printf("j = %d , t = %x \n", j, t);

return 0;
}

fwrite_test.c: In function ‘main':
fwrite_test.c:22: error: ‘FILE' has no member named ‘_p'
fwrite_test.c:27: error: ‘FILE' has no member named ‘_r'
fwrite_test.c:28: error: ‘FILE' has no member named ‘_p'