1UTIME(2) Linux Programmer's Manual UTIME(2)
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6 utime, utimes - change file last access and modification times
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9 #include <sys/types.h>
10 #include <utime.h>
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12 int utime(const char *filename, const struct utimbuf *times);
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14 #include <sys/time.h>
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16 int utimes(const char *filename, const struct timeval times[2]);
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19 Note: modern applications may prefer to use the interfaces described in
20 utimensat(2).
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22 The utime() system call changes the access and modification times of
23 the inode specified by filename to the actime and modtime fields of
24 times respectively.
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26 If times is NULL, then the access and modification times of the file
27 are set to the current time.
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29 Changing timestamps is permitted when: either the process has appropri‐
30 ate privileges, or the effective user ID equals the user ID of the
31 file, or times is NULL and the process has write permission for the
32 file.
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34 The utimbuf structure is:
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36 struct utimbuf {
37 time_t actime; /* access time */
38 time_t modtime; /* modification time */
39 };
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41 The utime() system call allows specification of timestamps with a reso‐
42 lution of 1 second.
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44 The utimes() system call is similar, but the times argument refers to
45 an array rather than a structure. The elements of this array are
46 timeval structures, which allow a precision of 1 microsecond for speci‐
47 fying timestamps. The timeval structure is:
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49 struct timeval {
50 long tv_sec; /* seconds */
51 long tv_usec; /* microseconds */
52 };
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54 times[0] specifies the new access time, and times[1] specifies the new
55 modification time. If times is NULL, then analogously to utime(), the
56 access and modification times of the file are set to the current time.
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59 On success, zero is returned. On error, -1 is returned, and errno is
60 set appropriately.
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63 EACCES Search permission is denied for one of the directories in the
64 path prefix of path (see also path_resolution(7)).
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66 EACCES times is NULL, the caller's effective user ID does not match the
67 owner of the file, the caller does not have write access to the
68 file, and the caller is not privileged (Linux: does not have
69 either the CAP_DAC_OVERRIDE or the CAP_FOWNER capability).
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71 ENOENT filename does not exist.
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73 EPERM times is not NULL, the caller's effective UID does not match the
74 owner of the file, and the caller is not privileged (Linux: does
75 not have the CAP_FOWNER capability).
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77 EROFS path resides on a read-only filesystem.
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80 utime(): SVr4, POSIX.1-2001. POSIX.1-2008 marks utime() as obsolete.
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82 utimes(): 4.3BSD, POSIX.1-2001.
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85 Linux does not allow changing the timestamps on an immutable file, or
86 setting the timestamps to something other than the current time on an
87 append-only file.
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90 chattr(1), touch(1), futimesat(2), stat(2), utimensat(2), futimens(3),
91 futimes(3), inode(7)
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94 This page is part of release 5.02 of the Linux man-pages project. A
95 description of the project, information about reporting bugs, and the
96 latest version of this page, can be found at
97 https://www.kernel.org/doc/man-pages/.
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101Linux 2017-09-15 UTIME(2)