Ausam/include/stdio.h
#define BUFSIZ 512
#define _NFILE 20
# ifndef FILE
extern struct _iobuf {
char *_ptr;
int _cnt;
char *_base;
char _flag;
char _file;
} _iob[_NFILE];
# endif
#define _IOREAD 01
#define _IOWRT 02
#define _IONBF 04
#define _IOMYBUF 010
#define _IOEOF 020
#define _IOERR 040
#define _IOSTRG 0100
#define NULL 0
#define FILE struct _iobuf
#define EOF (-1)
#define stdin (&_iob[0])
#define stdout (&_iob[1])
#define stderr (&_iob[2])
#define getc(p) (--(p)->_cnt>=0? *(p)->_ptr++&0377:_filbuf(p))
#define getchar() getc(stdin)
#define putc(x,p) (--(p)->_cnt>=0? (*(p)->_ptr++=(x)):_flsbuf((x),p))
#define putchar(x) putc(x,stdout)
#define feof(p) (((p)->_flag&_IOEOF)!=0)
#define ferror(p) (((p)->_flag&_IOERR)!=0)
#define fileno(p) p->_file
#define isdigit(c) (('0'<=c)&&(c<='9'))
#define isupper(c) (('A'<=c)&&(c<='Z'))
#define islower(c) (('a'<=c)&&(c<='z'))
#define isalpha(c) ( (('A'<=c)&&(c<='Z')) || (('a'<=c)&&(c<='z')) )
#define isspace(c) ((c==' ')||(c=='\t')||(c=='\n')||(c=='\r')||(c==014))||(c==013))
#define tolower(c) (c - 'A' + 'a')
#define toupper(c) (c - 'a' + 'A')