NAME

       utime, utimes - change file last access and modification times

LIBRARY

       Standard C library (libc, -lc)

SYNOPSIS

       #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

       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

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

ERRORS

       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

       POSIX.1-2008.

HISTORY

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

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

NOTES

       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

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