1UTIME(3P) POSIX Programmer's Manual UTIME(3P)
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6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
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13 utime — set file access and modification times
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16 #include <utime.h>
17 int utime(const char *path, const struct utimbuf *times);
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21 The utime() function shall set the access and modification times of the
22 file named by the path argument.
23 If times is a null pointer, the access and modification times of the
25 file shall be set to the current time. The effective user ID of the
26 process shall match the owner of the file, or the process has write
27 permission to the file or has appropriate privileges, to use utime() in
28 this manner.
29 If times is not a null pointer, times shall be interpreted as a pointer
31 to a utimbuf structure and the access and modification times shall be
32 set to the values contained in the designated structure. Only a process
33 with the effective user ID equal to the user ID of the file or a
34 process with appropriate privileges may use utime() this way.
35 The utimbuf structure is defined in the <utime.h> header. The times in
37 the structure utimbuf are measured in seconds since the Epoch.
38 Upon successful completion, the utime() function shall mark the last
40 file status change timestamp for update; see <sys/stat.h>.
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43 Upon successful completion, 0 shall be returned. Otherwise, −1 shall be
44 returned and errno shall be set to indicate the error, and the file
45 times shall not be affected.
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48 The utime() function shall fail if:
49 EACCES Search permission is denied by a component of the path prefix;
51 or the times argument is a null pointer and the effective user
52 ID of the process does not match the owner of the file, the
53 process does not have write permission for the file, and the
54 process does not have appropriate privileges.
55 ELOOP A loop exists in symbolic links encountered during resolution of
57 the path argument.
58 ENAMETOOLONG
60 The length of a component of a pathname is longer than
61 {NAME_MAX}.
62 ENOENT A component of path does not name an existing file or path is an
64 empty string.
65 ENOTDIR
67 A component of the path prefix names an existing file that is
68 neither a directory nor a symbolic link to a directory, or the
69 path argument contains at least one non-<slash> character and
70 ends with one or more trailing <slash> characters and the last
71 pathname component names an existing file that is neither a
72 directory nor a symbolic link to a directory.
73 EPERM The times argument is not a null pointer and the effective user
75 ID of the calling process does not match the owner of the file
76 and the calling process does not have appropriate privileges.
77 EROFS The file system containing the file is read-only.
79 The utime() function may fail if:
81 ELOOP More than {SYMLOOP_MAX} symbolic links were encountered during
83 resolution of the path argument.
84 ENAMETOOLONG
86 The length of a pathname exceeds {PATH_MAX}, or pathname resolu‐
87 tion of a symbolic link produced an intermediate result with a
88 length that exceeds {PATH_MAX}.
89 The following sections are informative.
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93 None.
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96 Since the utimbuf structure only contains time_t variables and is not
97 accurate to fractions of a second, applications should use the utimen‐
98 sat() function instead of the obsolescent utime() function.
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101 The actime structure member must be present so that an application may
102 set it, even though an implementation may ignore it and not change the
103 last data access timestamp on the file. If an application intends to
104 leave one of the times of a file unchanged while changing the other, it
105 should use stat() or fstat() to retrieve the file's st_atim and st_mtim
106 parameters, set actime and modtime in the buffer, and change one of
107 them before making the utime() call.
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110 The utime() function may be removed in a future version.
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113 fstat(), fstatat(), futimens()
114 The Base Definitions volume of POSIX.1‐2008, <sys_stat.h>, <utime.h>
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118 Portions of this text are reprinted and reproduced in electronic form
119 from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
120 -- Portable Operating System Interface (POSIX), The Open Group Base
121 Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
122 cal and Electronics Engineers, Inc and The Open Group. (This is
123 POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
124 event of any discrepancy between this version and the original IEEE and
125 The Open Group Standard, the original IEEE and The Open Group Standard
126 is the referee document. The original Standard can be obtained online
127 at http://www.unix.org/online.html .
128 Any typographical or formatting errors that appear in this page are
130 most likely to have been introduced during the conversion of the source
131 files to man page format. To report such errors, see https://www.ker‐
132 nel.org/doc/man-pages/reporting_bugs.html .
133IEEE/The Open Group 2013 UTIME(3P)