5 * According to X3J11, there is only one i/o buffer
6 * and it must not be occupied by both input and output data.
7 * If rp<wp, we must have state==RD and
8 * if wp<rp, we must have state==WR, so that getc and putc work correctly.
9 * On open, rp, wp and buf are set to 0, so first getc or putc will call _IO_getc
10 * or _IO_putc, which will allocate the buffer.
11 * If setvbuf(., ., _IONBF, .) is called, bufl is set to 0 and
12 * buf, rp and wp are pointed at unbuf.
13 * If setvbuf(., ., _IOLBF, .) is called, _IO_putc leaves wp and rp pointed at the
14 * end of the buffer so that it can be called on each putc to check whether it's got
15 * a newline. This nonsense is in order to avoid impacting performance of the other
16 * buffering modes more than necessary -- putting the test in putc adds many
17 * instructions that are wasted in non-_IOLBF mode:
18 * #define putc(c, f) (_IO_ctmp=(c),\
19 * (f)->wp>=(f)->rp || (f)->flags&LINEBUF && _IO_ctmp=='\n'\
20 * ?_IO_putc(_IO_ctmp, f)\
21 * :*(f)->wp++=_IO_ctmp)
25 int fd; /* UNIX file pointer */
26 char flags; /* bits for must free buffer on close, line-buffered */
27 char state; /* last operation was read, write, position, error, eof */
28 char *buf; /* pointer to i/o buffer */
29 char *rp; /* read pointer (or write end-of-buffer) */
30 char *wp; /* write pointer (or read end-of-buffer) */
31 char *lp; /* actual write pointer used when line-buffering */
32 long bufl; /* actual length of buffer */
33 char unbuf[1]; /* tiny buffer for unbuffered io (used for ungetc?) */
40 * Third arg of setvbuf
42 #define _IOFBF 1 /* block-buffered */
43 #define _IOLBF 2 /* line-buffered */
44 #define _IONBF 3 /* unbuffered */
45 #define BUFSIZ 4096 /* size of setbuf buffer */
46 #define EOF (-1) /* returned on end of file */
47 #define FOPEN_MAX 128 /* max files open */
48 #define FILENAME_MAX BUFSIZ /* silly filename length */
49 #define L_tmpnam 20 /* sizeof "/tmp/abcdefghij9999 */
53 #define TMP_MAX 64 /* very hard to set correctly */
54 #define stderr (&_IO_stream[2])
55 #define stdin (&_IO_stream[0])
56 #define stdout (&_IO_stream[1])
57 #define _IO_CHMASK 0377 /* mask for 8 bit characters */
62 FILE *fopen(const char *, const char *);
63 FILE *freopen(const char *, const char *, FILE *);
64 void setbuf(FILE *, char *);
65 int setvbuf(FILE *, char *, int, long);
66 int fprintf(FILE *, const char *, ...);
67 int fscanf(FILE *, const char *, ...);
68 int printf(const char *, ...);
69 int scanf(const char *, ...);
70 int sprintf(char *, const char *, ...);
71 int sscanf(const char *, const char *, ...);
72 int vfprintf(FILE *, const char *, va_list);
73 int vprintf(const char *, va_list);
74 int vsprintf(char *, const char *, va_list);
75 int vfscanf(FILE *, const char *, va_list);
77 char *fgets(char *, int, FILE *);
78 int fputc(int, FILE *);
79 int fputs(const char *, FILE *);
81 #define getc(f) ((f)->rp>=(f)->wp?_IO_getc(f):*(f)->rp++&_IO_CHMASK)
82 int _IO_getc(FILE *f);
84 #define getchar() getc(stdin)
86 int putc(int, FILE *);
87 #define putc(c, f) ((f)->wp>=(f)->rp?_IO_putc(c, f):(*(f)->wp++=c)&_IO_CHMASK)
88 int _IO_putc(int, FILE *);
90 #define putchar(c) putc(c, stdout)
91 int puts(const char *);
92 int ungetc(int, FILE *);
93 long fread(void *, long, long, FILE *);
94 long fwrite(const void *, long, long, FILE *);
95 int fgetpos(FILE *, fpos_t *);
96 int fseek(FILE *, long int, int);
97 int fsetpos(FILE *, const fpos_t *);
98 long int ftell(FILE *);
100 void clearerr(FILE *);
103 void perror(const char *);
104 extern FILE _IO_stream[FOPEN_MAX];
105 FILE *sopenr(const char *);
107 char *sclose(FILE *);
108 char *dtoa(double, int, int, int*, int*, char**);
109 void freedtoa(char*);