utime, utimes - change file last access and modification times
#include <sys/types.h>
#include <utime.h>
int utime(const char *filename, const struct utimbuf *times);
#include <sys/time.h>
int utimes(const char *filename, const struct timeval times[2]);
Note: modern applications may prefer to use the interfaces described in utimensat(2).
The utime() system call changes the access and modification times of the inode specified by filename
to the actime
and modtime
fields of times
respectively.
If times
is NULL, then the access and modification times of the file are set to the current time.
Changing timestamps is permitted when: either the process has appropriate privileges, or the effective user ID equals the user ID of the file, or times
is NULL and the process has write permission for the file.
The utimbuf
structure is:
struct utimbuf {
time_t actime; /* access time */
time_t modtime; /* modification time */
};
The utime() system call allows specification of timestamps with a resolution of 1 second.
The utimes() system call is similar, but the times
argument refers to an array rather than a structure. The elements of this array are timeval
structures, which allow a precision of 1 microsecond for specifying timestamps. The timeval
structure is:
struct timeval {
long tv_sec; /* seconds */
long tv_usec; /* microseconds */
};
times[0]
specifies the new access time, and times[1]
specifies the new modification time. If times
is NULL, then analogously to utime(), the access and modification times of the file are set to the current time.
On success, zero is returned. On error, -1 is returned, and errno
is set appropriately.
Search permission is denied for one of the directories in the path prefix of path
(see also path_resolution(7)).
times
is NULL, the caller's effective user ID does not match the owner of the file, the caller does not have write access to the file, and the caller is not privileged (Linux: does not have either the CAP_DAC_OVERRIDE or the CAP_FOWNER capability).
filename
does not exist.
times
is not NULL, the caller's effective UID does not match the owner of the file, and the caller is not privileged (Linux: does not have the CAP_FOWNER capability).
path
resides on a read-only filesystem.
Linux does not allow changing the timestamps on an immutable file, or setting the timestamps to something other than the current time on an append-only file.
This page is part of release 5.10 of the Linux man-pages
project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.