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/* Copyright (C) 1991, 1992, 1996, 1998, 2001, 2006 Free Software Foundation, Inc.
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This file is derived from mkstemps.c from the GNU Libiberty Library
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which in turn is derived from the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Library General Public License as
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published by the Free Software Foundation; either version 2 of the
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License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Library General Public License for more details.
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You should have received a copy of the GNU Library General Public
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License along with the GNU C Library; see the file COPYING.LIB. If not,
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write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
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Boston, MA 02110-1301, USA.
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#include "libguile/__scm.h"
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#ifdef HAVE_SYS_TIME_H
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/* We provide this prototype to avoid compiler warnings. If this ever
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conflicts with a declaration in a system header file, we'll find
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out, because we should include that header file here. */
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/* Generate a unique temporary file name from TEMPLATE.
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TEMPLATE has the form:
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The last six characters of TEMPLATE must be "XXXXXX"; they are
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replaced with a string that makes the filename unique.
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Returns a file descriptor open on the file for reading and writing. */
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static const char letters[]
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= "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
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static scm_t_uint64 value;
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#ifdef HAVE_GETTIMEOFDAY
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len = strlen (template);
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|| strncmp (&template[len - 6], "XXXXXX", 6))
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XXXXXX = &template[len - 6];
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#ifdef HAVE_GETTIMEOFDAY
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/* Get some more or less random data. */
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gettimeofday (&tv, NULL);
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value += ((scm_t_uint64) tv.tv_usec << 16) ^ tv.tv_sec ^ getpid ();
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for (count = 0; count < TMP_MAX; ++count)
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scm_t_uint64 v = value;
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/* Fill in the random bits. */
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XXXXXX[0] = letters[v % 62];
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XXXXXX[1] = letters[v % 62];
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XXXXXX[2] = letters[v % 62];
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XXXXXX[3] = letters[v % 62];
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XXXXXX[4] = letters[v % 62];
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XXXXXX[5] = letters[v % 62];
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fd = open (template, O_RDWR|O_CREAT|O_EXCL, 0600);
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/* The file does not exist. */
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/* This is a random value. It is only necessary that the next
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TMP_MAX values generated by adding 7777 to VALUE are different
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with (module 2^32). */
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/* We return the null string if we can't find a unique file name. */