1RENAME(P) POSIX Programmer's Manual RENAME(P)
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6 rename - rename a file
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9 #include <stdio.h>
10 int rename(const char *old, const char *new);
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15 The rename() function shall change the name of a file. The old argument
16 points to the pathname of the file to be renamed. The new argument
17 points to the new pathname of the file.
18 If either the old or new argument names a symbolic link, rename() shall
20 operate on the symbolic link itself, and shall not resolve the last
21 component of the argument. If the old argument and the new argument
22 resolve to the same existing file, rename() shall return successfully
23 and perform no other action.
24 If the old argument points to the pathname of a file that is not a
26 directory, the new argument shall not point to the pathname of a direc‐
27 tory. If the link named by the new argument exists, it shall be removed
28 and old renamed to new. In this case, a link named new shall remain
29 visible to other processes throughout the renaming operation and refer
30 either to the file referred to by new or old before the operation
31 began. Write access permission is required for both the directory con‐
32 taining old and the directory containing new.
33 If the old argument points to the pathname of a directory, the new
35 argument shall not point to the pathname of a file that is not a direc‐
36 tory. If the directory named by the new argument exists, it shall be
37 removed and old renamed to new. In this case, a link named new shall
38 exist throughout the renaming operation and shall refer either to the
39 directory referred to by new or old before the operation began. If new
40 names an existing directory, it shall be required to be an empty direc‐
41 tory.
42 If the old argument points to a pathname of a symbolic link, the sym‐
44 bolic link shall be renamed. If the new argument points to a pathname
45 of a symbolic link, the symbolic link shall be removed.
46 The new pathname shall not contain a path prefix that names old. Write
48 access permission is required for the directory containing old and the
49 directory containing new. If the old argument points to the pathname
50 of a directory, write access permission may be required for the direc‐
51 tory named by old, and, if it exists, the directory named by new.
52 If the link named by the new argument exists and the file's link count
54 becomes 0 when it is removed and no process has the file open, the
55 space occupied by the file shall be freed and the file shall no longer
56 be accessible. If one or more processes have the file open when the
57 last link is removed, the link shall be removed before rename()
58 returns, but the removal of the file contents shall be postponed until
59 all references to the file are closed.
60 Upon successful completion, rename() shall mark for update the st_ctime
62 and st_mtime fields of the parent directory of each file.
63 If the rename() function fails for any reason other than [EIO], any
65 file named by new shall be unaffected.
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68 Upon successful completion, rename() shall return 0; otherwise, -1
69 shall be returned, errno shall be set to indicate the error, and
70 neither the file named by old nor the file named by new shall be
71 changed or created.
72
74 The rename() function shall fail if:
75 EACCES A component of either path prefix denies search permission; or
77 one of the directories containing old or new denies write per‐
78 missions; or, write permission is required and is denied for a
79 directory pointed to by the old or new arguments.
80 EBUSY The directory named by old or new is currently in use by the
82 system or another process, and the implementation considers this
83 an error.
84 EEXIST or ENOTEMPTY
86 The link named by new is a directory that is not an empty direc‐
88 tory.
89 EINVAL The new directory pathname contains a path prefix that names the
91 old directory.
92 EIO A physical I/O error has occurred.
94 EISDIR The new argument points to a directory and the old argument
96 points to a file that is not a directory.
97 ELOOP A loop exists in symbolic links encountered during resolution of
99 the path argument.
100 EMLINK The file named by old is a directory, and the link count of the
102 parent directory of new would exceed {LINK_MAX}.
103 ENAMETOOLONG
105 The length of the old or new argument exceeds {PATH_MAX} or a
107 pathname component is longer than {NAME_MAX}.
108 ENOENT The link named by old does not name an existing file, or either
110 old or new points to an empty string.
111 ENOSPC The directory that would contain new cannot be extended.
113 ENOTDIR
115 A component of either path prefix is not a directory; or the old
116 argument names a directory and new argument names a non-direc‐
117 tory file.
118 EPERM or EACCES
120 The S_ISVTX flag is set on the directory containing the file
122 referred to by old and the caller is not the file owner, nor is
123 the caller the directory owner, nor does the caller have appro‐
124 priate privileges; or new refers to an existing file, the
125 S_ISVTX flag is set on the directory containing this file, and
126 the caller is not the file owner, nor is the caller the direc‐
127 tory owner, nor does the caller have appropriate privileges.
128 EROFS The requested operation requires writing in a directory on a
130 read-only file system.
131 EXDEV The links named by new and old are on different file systems and
133 the implementation does not support links between file systems.
134 The rename() function may fail if:
137 EBUSY The file named by the old or new arguments is a named STREAM.
139 ELOOP More than {SYMLOOP_MAX} symbolic links were encountered during
141 resolution of the path argument.
142 ENAMETOOLONG
144 As a result of encountering a symbolic link in resolution of the
146 path argument, the length of the substituted pathname string
147 exceeded {PATH_MAX}.
148 ETXTBSY
150 The file to be renamed is a pure procedure (shared text) file
151 that is being executed.
152 The following sections are informative.
155
157 Renaming a File
158 The following example shows how to rename a file named /home/cnd/mod1
159 to /home/cnd/mod2.
160 #include <stdio.h>
163 int status;
166 ...
167 status = rename("/home/cnd/mod1", "/home/cnd/mod2");
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170 Some implementations mark for update the st_ctime field of renamed
171 files and some do not. Applications which make use of the st_ctime
172 field may behave differently with respect to renamed files unless they
173 are designed to allow for either behavior.
174
176 This rename() function is equivalent for regular files to that defined
177 by the ISO C standard. Its inclusion here expands that definition to
178 include actions on directories and specifies behavior when the new
179 parameter names a file that already exists. That specification requires
180 that the action of the function be atomic.
181 One of the reasons for introducing this function was to have a means of
183 renaming directories while permitting implementations to prohibit the
184 use of link() and unlink() with directories, thus constraining links to
185 directories to those made by mkdir().
186 The specification that if old and new refer to the same file is
188 intended to guarantee that:
189 rename("x", "x");
192 does not remove the file.
194 Renaming dot or dot-dot is prohibited in order to prevent cyclical file
196 system paths.
197 See also the descriptions of [ENOTEMPTY] and [ENAMETOOLONG] in rmdir()
199 and [EBUSY] in unlink() . For a discussion of [EXDEV], see link() .
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202 None.
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205 link() , rmdir() , symlink() , unlink() , the Base Definitions volume
206 of IEEE Std 1003.1-2001, <stdio.h>
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209 Portions of this text are reprinted and reproduced in electronic form
210 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
211 -- Portable Operating System Interface (POSIX), The Open Group Base
212 Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
213 Electrical and Electronics Engineers, Inc and The Open Group. In the
214 event of any discrepancy between this version and the original IEEE and
215 The Open Group Standard, the original IEEE and The Open Group Standard
216 is the referee document. The original Standard can be obtained online
217 at http://www.opengroup.org/unix/online.html .
218IEEE/The Open Group 2003 RENAME(P)