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

       utime(): SVr4, POSIX.1-2001.  POSIX.1-2008 marks utime() 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)