1 /* Copyright (C) 1991-2023 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
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.
8
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.
13
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 <https://www.gnu.org/licenses/>. */
17
18 #ifndef _SYS_UIO_H
19 #define _SYS_UIO_H 1
20
21 #include <features.h>
22 #include <sys/types.h>
23 #include <bits/types/struct_iovec.h>
24 #include <bits/uio_lim.h>
25 #ifdef __IOV_MAX
26 # define UIO_MAXIOV __IOV_MAX
27 #else
28 # undef UIO_MAXIOV
29 #endif
30
31 __BEGIN_DECLS
32
33 /* Read data from file descriptor FD, and put the result in the
34 buffers described by IOVEC, which is a vector of COUNT 'struct iovec's.
35 The buffers are filled in the order specified.
36 Operates just like 'read' (see <unistd.h>) except that data are
37 put in IOVEC instead of a contiguous buffer.
38
39 This function is a cancellation point and therefore not marked with
40 __THROW. */
41 extern ssize_t readv (int __fd, const struct iovec *__iovec, int __count)
42 __wur __attr_access ((__read_only__, 2, 3));
43
44 /* Write data pointed by the buffers described by IOVEC, which
45 is a vector of COUNT 'struct iovec's, to file descriptor FD.
46 The data is written in the order specified.
47 Operates just like 'write' (see <unistd.h>) except that the data
48 are taken from IOVEC instead of a contiguous buffer.
49
50 This function is a cancellation point and therefore not marked with
51 __THROW. */
52 extern ssize_t writev (int __fd, const struct iovec *__iovec, int __count)
53 __wur __attr_access ((__read_only__, 2, 3));
54
55
56 #ifdef __USE_MISC
57 # ifndef __USE_FILE_OFFSET64
58 /* Read data from file descriptor FD at the given position OFFSET
59 without change the file pointer, and put the result in the buffers
60 described by IOVEC, which is a vector of COUNT 'struct iovec's.
61 The buffers are filled in the order specified. Operates just like
62 'pread' (see <unistd.h>) except that data are put in IOVEC instead
63 of a contiguous buffer.
64
65 This function is a cancellation point and therefore not marked with
66 __THROW. */
67 extern ssize_t preadv (int __fd, const struct iovec *__iovec, int __count,
68 __off_t __offset)
69 __wur __attr_access ((__read_only__, 2, 3));
70
71 /* Write data pointed by the buffers described by IOVEC, which is a
72 vector of COUNT 'struct iovec's, to file descriptor FD at the given
73 position OFFSET without change the file pointer. The data is
74 written in the order specified. Operates just like 'pwrite' (see
75 <unistd.h>) except that the data are taken from IOVEC instead of a
76 contiguous buffer.
77
78 This function is a cancellation point and therefore not marked with
79 __THROW. */
80 extern ssize_t pwritev (int __fd, const struct iovec *__iovec, int __count,
81 __off_t __offset)
82 __wur __attr_access ((__read_only__, 2, 3));
83
84 # else
85 # ifdef __REDIRECT
86 extern ssize_t __REDIRECT (preadv, (int __fd, const struct iovec *__iovec,
87 int __count, __off64_t __offset),
88 preadv64)
89 __wur __attr_access ((__read_only__, 2, 3));
90 extern ssize_t __REDIRECT (pwritev, (int __fd, const struct iovec *__iovec,
91 int __count, __off64_t __offset),
92 pwritev64)
93 __wur __attr_access ((__read_only__, 2, 3));
94 # else
95 # define preadv preadv64
96 # define pwritev pwritev64
97 # endif
98 # endif
99
100 # ifdef __USE_LARGEFILE64
101 /* Read data from file descriptor FD at the given position OFFSET
102 without change the file pointer, and put the result in the buffers
103 described by IOVEC, which is a vector of COUNT 'struct iovec's.
104 The buffers are filled in the order specified. Operates just like
105 'pread' (see <unistd.h>) except that data are put in IOVEC instead
106 of a contiguous buffer.
107
108 This function is a cancellation point and therefore not marked with
109 __THROW. */
110 extern ssize_t preadv64 (int __fd, const struct iovec *__iovec, int __count,
111 __off64_t __offset)
112 __wur __attr_access ((__read_only__, 2, 3));
113
114 /* Write data pointed by the buffers described by IOVEC, which is a
115 vector of COUNT 'struct iovec's, to file descriptor FD at the given
116 position OFFSET without change the file pointer. The data is
117 written in the order specified. Operates just like 'pwrite' (see
118 <unistd.h>) except that the data are taken from IOVEC instead of a
119 contiguous buffer.
120
121 This function is a cancellation point and therefore not marked with
122 __THROW. */
123 extern ssize_t pwritev64 (int __fd, const struct iovec *__iovec, int __count,
124 __off64_t __offset)
125 __wur __attr_access ((__read_only__, 2, 3));
126 # endif
127 #endif /* Use misc. */
128
129
130 #ifdef __USE_GNU
131 # ifndef __USE_FILE_OFFSET64
132 /* Same as preadv but with an additional flag argumenti defined at uio.h. */
133 extern ssize_t preadv2 (int __fp, const struct iovec *__iovec, int __count,
134 __off_t __offset, int ___flags)
135 __wur __attr_access ((__read_only__, 2, 3));
136
137 /* Same as preadv but with an additional flag argument defined at uio.h. */
138 extern ssize_t pwritev2 (int __fd, const struct iovec *__iodev, int __count,
139 __off_t __offset, int __flags) __wur;
140
141 # else
142 # ifdef __REDIRECT
143 extern ssize_t __REDIRECT (pwritev2, (int __fd, const struct iovec *__iovec,
144 int __count, __off64_t __offset,
145 int __flags),
146 pwritev64v2)
147 __wur __attr_access ((__read_only__, 2, 3));
148 extern ssize_t __REDIRECT (preadv2, (int __fd, const struct iovec *__iovec,
149 int __count, __off64_t __offset,
150 int __flags),
151 preadv64v2)
152 __wur __attr_access ((__read_only__, 2, 3));
153 # else
154 # define preadv2 preadv64v2
155 # define pwritev2 pwritev64v2
156 # endif
157 # endif
158
159 # ifdef __USE_LARGEFILE64
160 /* Same as preadv but with an additional flag argumenti defined at uio.h. */
161 extern ssize_t preadv64v2 (int __fp, const struct iovec *__iovec,
162 int __count, __off64_t __offset,
163 int ___flags)
164 __wur __attr_access ((__read_only__, 2, 3));
165
166 /* Same as preadv but with an additional flag argument defined at uio.h. */
167 extern ssize_t pwritev64v2 (int __fd, const struct iovec *__iodev,
168 int __count, __off64_t __offset,
169 int __flags)
170 __wur __attr_access ((__read_only__, 2, 3));
171 # endif
172 #endif /* Use GNU. */
173
174 __END_DECLS
175
176 /* Some operating systems provide system-specific extensions to this
177 header. */
178 #ifdef __USE_GNU
179 # include <bits/uio-ext.h>
180 #endif
181
182 #endif /* sys/uio.h */