utime(2) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | STANDARDS | HISTORY | NOTES | SEE ALSO

utime(2)                   System Calls Manual                  utime(2)

NAME         top

       utime, utimes - change file last access and modification times

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <utime.h>

       int utime(const char *filename,
                 const struct utimbuf *_Nullable times);

       #include <sys/time.h>

       int utimes(const char *filename,
                 const struct timeval times[_Nullable 2]);

DESCRIPTION         top

       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.  The status change time (ctime)
       will be set to the current time, even if the other time stamps
       don't actually change.

       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.

RETURN VALUE         top

       On success, zero is returned.  On error, -1 is returned, and
       errno is set to indicate the error.

ERRORS         top

       EACCES Search permission is denied for one of the directories in
              the path prefix of path (see also path_resolution(7)).

       EACCES 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).

       ENOENT filename does not exist.

       EPERM  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).

       EROFS  path resides on a read-only filesystem.

STANDARDS         top

       POSIX.1-2008.

HISTORY         top

       utime()
              SVr4, POSIX.1-2001.  POSIX.1-2008 marks it as obsolete.

       utimes()
              4.3BSD, POSIX.1-2001.

NOTES         top

       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.

SEE ALSO         top

       chattr(1), touch(1), futimesat(2), stat(2), utimensat(2),
       futimens(3), futimes(3), inode(7)

Linux man-pages (unreleased)     (date)                         utime(2)

Pages that refer to this page: indent(1)fcntl(2)futimesat(2)stat(2)statx(2)syscalls(2)utimensat(2)ctime(3)futimes(3)timeval(3type)capabilities(7)inode(7)landlock(7)signal-safety(7)time(7)mount(8)