The utimes function sets the access and modification times of the file pointed to by the path argument to the value of the times argument. The utimes function allows time specifications accurate to the microsecond. If the times argument is a NULL pointer, the access and modification times of the file are set to the current time. The effective user ID of the process must be the same as the owner of the file, or must have write access to the file or appropriate privileges to use this call in this manner. Upon completion, utimes marks the time of the last file status change, st_ctime, for update. NOTE (Integrity servers, Alpha) On OpenVMS Alpha and Integrity server systems, the stat, fstat, utime, and utimes functions have been enhanced to take advantage of the new file-system support for POSIX compliant file timestamps. This support is available only on ODS-5 devices on OpenVMS Alpha systems beginning with a version of OpenVMS Alpha after Version 7.3. Before this change, the stat and fstat functions were setting the values of the st_ctime, st_mtime, and st_atime fields based on the following file attributes: st_ctime - ATR$C_CREDATE (file creation time) st_mtime - ATR$C_REVDATE (file revision time) st_atime - was always set to st_mtime because no support for file access time was available Also, for the file-modification time, utime and utimes were modifying the ATR$C_REVDATE file attribute, and ignoring the file-access-time argument. After the change, for a file on an ODS-5 device, the stat and fstat functions set the values of the st_ctime, st_ mtime, and st_atime fields based on the following new file attributes: st_ctime - ATR$C_ATTDATE (last attribute modification time) st_mtime - ATR$C_MODDATE (last data modification time) st_atime - ATR$C_ACCDATE (last access time) If ATR$C_ACCDATE is 0, as on an ODS-2 device, the stat and fstat functions set st_atime to st_mtime. For the file-modification time, the utime and utimes functions modify both the ATR$C_REVDATE and ATR$C_MODDATE file attributes. For the file-access time, these functions modify the ATR$C_ACCDATE file attribute. Setting the ATR$C_ MODDATE and ATR$C_ACCDATE file attributes on an ODS-2 device has no effect. For compatibility, the old behavior of stat, fstat, utime, and utimes remains the default, regardless of the kind of device. The new behavior must be explicitly enabled by defining the DECC$EFS_FILE_TIMESTAMPS logical name to "ENABLE" before invoking the application. Setting this logical does not affect the behavior of stat, fstat, utime, and utimes for files on an ODS-2 device.