1 /* Copyright (C) 1993-2014 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <http://www.gnu.org/licenses/>.
18 As a special exception, if you link the code in this file with
19 files compiled with a GNU compiler to produce an executable,
20 that does not cause the resulting executable to be covered by
21 the GNU Lesser General Public License. This exception does not
22 however invalidate any other reasons why the executable file
23 might be covered by the GNU Lesser General Public License.
24 This exception applies to code released by its copyright holders
25 in files containing the exception. */
29 #define _IOFBF 0 /* Fully buffered. */
30 #define _IOLBF 1 /* Line buffered. */
31 #define _IONBF 2 /* No buffering. */
34 _IO_setvbuf (fp, buf, mode, size)
42 _IO_acquire_lock (fp);
46 fp->_IO_file_flags &= ~(_IO_LINE_BUF|_IO_UNBUFFERED);
49 if (fp->_IO_buf_base == NULL)
51 /* There is no flag to distinguish between "fully buffered
52 mode has been explicitly set" as opposed to "line
53 buffering has not been explicitly set". In both
54 cases, _IO_LINE_BUF is off. If this is a tty, and
55 _IO_filedoalloc later gets called, it cannot know if
56 it should set the _IO_LINE_BUF flag (because that is
57 the default), or not (because we have explicitly asked
58 for fully buffered mode). So we make sure a buffer
59 gets allocated now, and explicitly turn off line
62 A possibly cleaner alternative would be to add an
63 extra flag, but then flags are a finite resource. */
64 if (_IO_DOALLOCATE (fp) < 0)
69 fp->_IO_file_flags &= ~_IO_LINE_BUF;
76 fp->_IO_file_flags &= ~_IO_UNBUFFERED;
77 fp->_IO_file_flags |= _IO_LINE_BUF;
85 fp->_IO_file_flags &= ~_IO_LINE_BUF;
86 fp->_IO_file_flags |= _IO_UNBUFFERED;
94 result = _IO_SETBUF (fp, buf, size) == NULL ? EOF : 0;
97 _IO_release_lock (fp);
100 libc_hidden_def (_IO_setvbuf)
103 weak_alias (_IO_setvbuf, setvbuf)