usr/src/lib/libbc/libc/compat/common/utime.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 1987 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <sys/types.h>
  30 #include <sys/time.h>
  31
  32 /*
  33  * Backwards compatible utime.
  34  *
  35  * The System V system call allows any user with write permission
  36  * on a file to set the accessed and modified times to the current
  37  * time; they specify this by passing a null pointer to "utime".
  38  * This is done to simulate reading one byte from a file and
  39  * overwriting that byte with itself, which is the technique used
  40  * by older versions of the "touch" command.  The advantage of this
  41  * hack in the system call is that it works correctly even if the file
  42  * is zero-length.
  43  *
  44  * The BSD system call never allowed a null pointer so there should
  45  * be no compatibility problem there.
  46  */
  47
  48 int
  49 utime(char *name, time_t otv[2])
  50 {
  51         struct timeval tv[2];
  52
  53         if (otv == 0) {
  54                 return (utimes(name, (struct timeval *)0));
  55         } else {
  56                 tv[0].tv_sec = (long)otv[0];
  57                 tv[0].tv_usec = 0;
  58                 tv[1].tv_sec = (long)otv[1];
  59                 tv[1].tv_usec = 0;
  60         }
  61         return (utimes(name, tv));
  62 }