UTIME(2)                                            Linux Programmer's Manual                                           UTIME(2)



NAME
       utime, utimes - change file last access and modification times

SYNOPSIS
       #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]);

DESCRIPTION
       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 analo-
       gously 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 appropriately.

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  privi-
              leged (Linux: does not have the CAP_FOWNER capability).

       EROFS  path resides on a read-only file system.

CONFORMING TO
       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.

       In libc4 and libc5, utimes() is just a wrapper for utime() and hence does not allow a subsecond resolution.

SEE ALSO
       chattr(1), futimesat(2), stat(2), utimensat(2), futimes(3), futimens(3)

COLOPHON
       This page is part of release 3.25 of the Linux man-pages project.  A description of the project,  and  information  about
       reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.



Linux                                                      2008-08-06                                                   UTIME(2)