Subversion Repositories Kolibri OS

Rev

Rev 4874 | Only display areas with differences | Regard whitespace | Details | Blame | Last modification | View Log | RSS feed

Rev 4874 Rev 4921
1 
/*
 1 
/*
2 
 * Copyright (c) 1990 The Regents of the University of California.
 2 
 * Copyright (c) 1990 The Regents of the University of California.
3 
 * All rights reserved.
 3 
 * All rights reserved.
4 
 *
 4 
 *
5 
 * Redistribution and use in source and binary forms are permitted
 5 
 * Redistribution and use in source and binary forms are permitted
6 
 * provided that the above copyright notice and this paragraph are
 6 
 * provided that the above copyright notice and this paragraph are
7 
 * duplicated in all such forms and that any documentation,
 7 
 * duplicated in all such forms and that any documentation,
8 
 * advertising materials, and other materials related to such
 8 
 * advertising materials, and other materials related to such
9 
 * distribution and use acknowledge that the software was developed
 9 
 * distribution and use acknowledge that the software was developed
10 
 * by the University of California, Berkeley.  The name of the
 10 
 * by the University of California, Berkeley.  The name of the
11 
 * University may not be used to endorse or promote products derived
 11 
 * University may not be used to endorse or promote products derived
12 
 * from this software without specific prior written permission.
 12 
 * from this software without specific prior written permission.
13 
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 13 
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14 
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 14 
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15 
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 15 
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16 
 */
 16 
 */
17 
 
 17 
 
18 
/*
 18 
/*
19 
FUNCTION
 19 
FUNCTION
20 
<>, <>---return position in a stream or file
 20 
<>, <>---return position in a stream or file
21 
 
 21 
 
22 
INDEX
 22 
INDEX
23 
	ftell
 23 
	ftell
24 
INDEX
 24 
INDEX
25 
	ftello
 25 
	ftello
26 
INDEX
 26 
INDEX
27 
	_ftell_r
 27 
	_ftell_r
28 
INDEX
 28 
INDEX
29 
	_ftello_r
 29 
	_ftello_r
30 
 
 30 
 
31 
ANSI_SYNOPSIS
 31 
ANSI_SYNOPSIS
32 
	#include
32 
	#include
33 
	long ftell(FILE *<[fp]>);
 33 
	long ftell(FILE *<[fp]>);
34 
	off_t ftello(FILE *<[fp]>);
 34 
	off_t ftello(FILE *<[fp]>);
35 
	long _ftell_r(struct _reent *<[ptr]>, FILE *<[fp]>);
 35 
	long _ftell_r(struct _reent *<[ptr]>, FILE *<[fp]>);
36 
	off_t _ftello_r(struct _reent *<[ptr]>, FILE *<[fp]>);
 36 
	off_t _ftello_r(struct _reent *<[ptr]>, FILE *<[fp]>);
37 
 
 37 
 
38 
TRAD_SYNOPSIS
 38 
TRAD_SYNOPSIS
39 
	#include
39 
	#include
40 
	long ftell(<[fp]>)
 40 
	long ftell(<[fp]>)
41 
	FILE *<[fp]>;
 41 
	FILE *<[fp]>;
42 
 
 42 
 
43 
	off_t ftello(<[fp]>)
 43 
	off_t ftello(<[fp]>)
44 
	FILE *<[fp]>;
 44 
	FILE *<[fp]>;
45 
 
 45 
 
46 
	long _ftell_r(<[ptr]>, <[fp]>)
 46 
	long _ftell_r(<[ptr]>, <[fp]>)
47 
	struct _reent *<[ptr]>;
 47 
	struct _reent *<[ptr]>;
48 
	FILE *<[fp]>;
 48 
	FILE *<[fp]>;
49 
 
 49 
 
50 
	off_t _ftello_r(<[ptr]>, <[fp]>)
 50 
	off_t _ftello_r(<[ptr]>, <[fp]>)
51 
	struct _reent *<[ptr]>;
 51 
	struct _reent *<[ptr]>;
52 
	FILE *<[fp]>;
 52 
	FILE *<[fp]>;
53 
 
 53 
 
54 
DESCRIPTION
 54 
DESCRIPTION
55 
Objects of type <> can have a ``position'' that records how much
 55 
Objects of type <> can have a ``position'' that records how much
56 
of the file your program has already read.  Many of the <> functions
 56 
of the file your program has already read.  Many of the <> functions
57 
depend on this position, and many change it as a side effect.
 57 
depend on this position, and many change it as a side effect.
58 
 
 58 
 
59 
The result of <>/<> is the current position for a file
 59 
The result of <>/<> is the current position for a file
60 
identified by <[fp]>.  If you record this result, you can later
 60 
identified by <[fp]>.  If you record this result, you can later
61 
use it with <>/<> to return the file to this
 61 
use it with <>/<> to return the file to this
62 
position.  The difference between <> and <> is that
 62 
position.  The difference between <> and <> is that
63 
<> returns <> and <> returns <>.
 63 
<> returns <> and <> returns <>.
64 
 
 64 
 
65 
In the current implementation, <>/<> simply uses a character
 65 
In the current implementation, <>/<> simply uses a character
66 
count to represent the file position; this is the same number that
 66 
count to represent the file position; this is the same number that
67 
would be recorded by <>.
 67 
would be recorded by <>.
68 
 
 68 
 
69 
RETURNS
 69 
RETURNS
70 
<>/<> return the file position, if possible.  If they cannot do
 70 
<>/<> return the file position, if possible.  If they cannot do
71 
this, they return <<-1L>>.  Failure occurs on streams that do not support
 71 
this, they return <<-1L>>.  Failure occurs on streams that do not support
72 
positioning; the global <> indicates this condition with the
 72 
positioning; the global <> indicates this condition with the
73 
value <>.
 73 
value <>.
74 
 
 74 
 
75 
PORTABILITY
 75 
PORTABILITY
76 
<> is required by the ANSI C standard, but the meaning of its
 76 
<> is required by the ANSI C standard, but the meaning of its
77 
result (when successful) is not specified beyond requiring that it be
 77 
result (when successful) is not specified beyond requiring that it be
78 
acceptable as an argument to <>.  In particular, other
 78 
acceptable as an argument to <>.  In particular, other
79 
conforming C implementations may return a different result from
 79 
conforming C implementations may return a different result from
80 
<> than what <> records.
 80 
<> than what <> records.
81 
 
 81 
 
82 
<> is defined by the Single Unix specification.
 82 
<> is defined by the Single Unix specification.
83 
 
 83 
 
84 
No supporting OS subroutines are required.
 84 
No supporting OS subroutines are required.
85 
*/
 85 
*/
86 
 
 86 
 
87 
#if defined(LIBC_SCCS) && !defined(lint)
 87 
#if defined(LIBC_SCCS) && !defined(lint)
88 
static char sccsid[] = "%W% (Berkeley) %G%";
 88 
static char sccsid[] = "%W% (Berkeley) %G%";
89 
#endif /* LIBC_SCCS and not lint */
 89 
#endif /* LIBC_SCCS and not lint */
90 
 
 90 
 
91 
/*
 91 
/*
92 
 * ftell: return current offset.
 92 
 * ftell: return current offset.
93 
 */
 93 
 */
94 
 
 94 
 
95 
#include <_ansi.h>
 95 
#include <_ansi.h>
96 
#include
96 
#include
97 
#include
97 
#include
98 
#include
98 
#include
99 
#include "local.h"
 99 
#include "local.h"
100 
 
 100 
 
101 
long
 101 
long
102 
_DEFUN(_ftell_r, (ptr, fp),
 102 
_DEFUN(_ftell_r, (ptr, fp),
103 
       struct _reent *ptr _AND
 103 
       struct _reent *ptr _AND
104 
       register FILE * fp)
 104 
       register FILE * fp)
105 
{
 105 
{
106 
  _fpos_t pos;
 106 
  _fpos_t pos;
107 
 
 - 
 
108 
  /* Ensure stdio is set up.  */
 - 
 
109 
 
 - 
 
110 
  CHECK_INIT (ptr, fp);
 - 
 
111 
 
 - 
 
112 
  _flockfile (fp);
 - 
 
113 
 
 - 
 
114 
  if (fp->_seek == NULL)
 - 
 
115 
    {
 - 
 
116 
      ptr->_errno = ESPIPE;
 - 
 
117 
      _funlockfile (fp);
 - 
 
118 
      return -1L;
 - 
 
119 
    }
 - 
 
120 
 
 - 
 
121 
  /* Find offset of underlying I/O object, then adjust for buffered
 - 
 
122 
     bytes.  Flush a write stream, since the offset may be altered if
 - 
 
123 
     the stream is appending.  Do not flush a read stream, since we
 - 
 
124 
     must not lose the ungetc buffer.  */
 - 
 
125 
  if (fp->_flags & __SWR)
 107 
 
126 
    _fflush_r (ptr, fp);
 - 
 
127 
  if (fp->_flags & __SOFF)
 - 
 
128 
    pos = fp->_offset;
 - 
 
129 
  else
 - 
 
130 
    {
 - 
 
131 
      pos = fp->_seek (ptr, fp->_cookie, (_fpos_t) 0, SEEK_CUR);
 - 
 
132 
      if (pos == -1L)
 - 
 
133 
        {
 - 
 
134 
          _funlockfile (fp);
 - 
 
135 
          return pos;
 - 
 
136 
        }
 - 
 
137 
    }
 - 
 
138 
  if (fp->_flags & __SRD)
 - 
 
139 
    {
 - 
 
140 
      /*
 - 
 
141 
       * Reading.  Any unread characters (including
 - 
 
142 
       * those from ungetc) cause the position to be
 - 
 
143 
       * smaller than that in the underlying object.
 - 
 
144 
       */
 - 
 
145 
      pos -= fp->_r;
 - 
 
146 
      if (HASUB (fp))
 - 
 
147 
	pos -= fp->_ur;
 - 
 
148 
    }
 - 
 
149 
  else if ((fp->_flags & __SWR) && fp->_p != NULL)
 - 
 
150 
    {
 - 
 
151 
      /*
 - 
 
152 
       * Writing.  Any buffered characters cause the
 - 
 
153 
       * position to be greater than that in the
 - 
 
154 
       * underlying object.
 - 
 
155 
       */
 - 
 
156 
      pos += fp->_p - fp->_bf._base;
 - 
 
157 
    }
 - 
 
158 
 
 - 
 
159 
  _funlockfile (fp);
 108 
  pos = _ftello_r (ptr, fp);
160 
  if ((long)pos != pos)
 109 
  if ((long)pos != pos)
161 
    {
 110 
    {
162 
      pos = -1;
 111 
      pos = -1;
163 
      ptr->_errno = EOVERFLOW;
 112 
      ptr->_errno = EOVERFLOW;
164 
    }
 113 
    }
165 
  return pos;
 114 
  return (long)pos;
166 
}
 115 
}
167 
 
 116 
 
168 
#ifndef _REENT_ONLY
 117 
#ifndef _REENT_ONLY
169 
 
 118 
 
170 
long
 119 
long
171 
_DEFUN(ftell, (fp),
 120 
_DEFUN(ftell, (fp),
172 
       register FILE * fp)
 121 
       register FILE * fp)
173 
{
 122 
{
174 
  return _ftell_r (_REENT, fp);
 123 
  return _ftell_r (_REENT, fp);
175 
}
 124 
}
176 
 
 125 
 
177 
#endif /* !_REENT_ONLY */
 126 
#endif /* !_REENT_ONLY */