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File::Temp(3)	       Perl Programmers	Reference Guide		 File::Temp(3)

NAME
       File::Temp - return name	and handle of a	temporary file safely

VERSION
       version 0.2304

SYNOPSIS
	 use File::Temp	qw/ tempfile tempdir /;

	 $fh = tempfile();
	 ($fh, $filename) = tempfile();

	 ($fh, $filename) = tempfile( $template, DIR =>	$dir);
	 ($fh, $filename) = tempfile( $template, SUFFIX	=> '.dat');
	 ($fh, $filename) = tempfile( $template, TMPDIR	=> 1 );

	 binmode( $fh, ":utf8" );

	 $dir =	tempdir( CLEANUP => 1 );
	 ($fh, $filename) = tempfile( DIR => $dir );

       Object interface:

	 require File::Temp;
	 use File::Temp	();
	 use File::Temp	qw/ :seekable /;

	 $fh = File::Temp->new();
	 $fname	= $fh->filename;

	 $fh = File::Temp->new(TEMPLATE	=> $template);
	 $fname	= $fh->filename;

	 $tmp =	File::Temp->new( UNLINK	=> 0, SUFFIX =>	'.dat' );
	 print $tmp "Some data\n";
	 print "Filename is $tmp\n";
	 $tmp->seek( 0,	SEEK_END );

       The following interfaces	are provided for compatibility with existing
       APIs. They should not be	used in	new code.

       MkTemp family:

	 use File::Temp	qw/ :mktemp  /;

	 ($fh, $file) =	mkstemp( "tmpfileXXXXX"	);
	 ($fh, $file) =	mkstemps( "tmpfileXXXXXX", $suffix);

	 $tmpdir = mkdtemp( $template );

	 $unopened_file	= mktemp( $template );

       POSIX functions:

	 use File::Temp	qw/ :POSIX /;

	 $file = tmpnam();
	 $fh = tmpfile();

	 ($fh, $file) =	tmpnam();

       Compatibility functions:

	 $unopened_file	= File::Temp::tempnam( $dir, $pfx );

DESCRIPTION
       "File::Temp" can	be used	to create and open temporary files in a	safe
       way.  There is both a function interface	and an object-oriented
       interface.  The File::Temp constructor or the tempfile()	function can
       be used to return the name and the open filehandle of a temporary file.
       The tempdir() function can be used to create a temporary	directory.

       The security aspect of temporary	file creation is emphasized such that
       a filehandle and	filename are returned together.	 This helps guarantee
       that a race condition can not occur where the temporary file is created
       by another process between checking for the existence of	the file and
       its opening.  Additional	security levels	are provided to	check, for
       example,	that the sticky	bit is set on world writable directories.  See
       "safe_level" for	more information.

       For compatibility with popular C	library	functions, Perl
       implementations of the mkstemp()	family of functions are	provided.
       These are, mkstemp(), mkstemps(), mkdtemp() and mktemp().

       Additionally, implementations of	the standard POSIX tmpnam() and
       tmpfile() functions are provided	if required.

       Implementations of mktemp(), tmpnam(), and tempnam() are	provided, but
       should be used with caution since they return only a filename that was
       valid when function was called, so cannot guarantee that	the file will
       not exist by the	time the caller	opens the filename.

       Filehandles returned by these functions support the seekable methods.

OBJECT-ORIENTED	INTERFACE
       This is the primary interface for interacting with "File::Temp".	Using
       the OO interface	a temporary file can be	created	when the object	is
       constructed and the file	can be removed when the	object is no longer
       required.

       Note that there is no method to obtain the filehandle from the
       "File::Temp" object. The	object itself acts as a	filehandle.  The
       object isa "IO::Handle" and isa "IO::Seekable" so all those methods are
       available.

       Also, the object	is configured such that	it stringifies to the name of
       the temporary file and so can be	compared to a filename directly.  It
       numifies	to the "refaddr" the same as other handles and so can be
       compared	to other handles with "==".

	   $fh eq $filename	  # as a string
	   $fh != \*STDOUT	  # as a number

       new Create a temporary file object.

	     my	$tmp = File::Temp->new();

	   by default the object is constructed	as if "tempfile" was called
	   without options, but	with the additional behaviour that the
	   temporary file is removed by	the object destructor if UNLINK	is set
	   to true (the	default).

	   Supported arguments are the same as for "tempfile": UNLINK
	   (defaulting to true), DIR, EXLOCK and SUFFIX. Additionally, the
	   filename template is	specified using	the TEMPLATE option. The OPEN
	   option is not supported (the	file is	always opened).

	    $tmp = File::Temp->new( TEMPLATE =>	'tempXXXXX',
				   DIR => 'mydir',
				   SUFFIX => '.dat');

	   Arguments are case insensitive.

	   Can call croak() if an error	occurs.

       newdir
	   Create a temporary directory	using an object	oriented interface.

	     $dir = File::Temp->newdir();

	   By default the directory is deleted when the	object goes out	of
	   scope.

	   Supports the	same options as	the "tempdir" function.	Note that
	   directories created with this method	default	to CLEANUP => 1.

	     $dir = File::Temp->newdir(	$template, %options );

	   A template may be specified either with a leading template or with
	   a TEMPLATE argument.

       filename
	   Return the name of the temporary file associated with this object
	   (if the object was created using the	"new" constructor).

	     $filename = $tmp->filename;

	   This	method is called automatically when the	object is used as a
	   string.

       dirname
	   Return the name of the temporary directory associated with this
	   object (if the object was created using the "newdir"	constructor).

	     $dirname =	$tmpdir->dirname;

	   This	method is called automatically when the	object is used in
	   string context.

       unlink_on_destroy
	   Control whether the file is unlinked	when the object	goes out of
	   scope.  The file is removed if this value is	true and $KEEP_ALL is
	   not.

	    $fh->unlink_on_destroy( 1 );

	   Default is for the file to be removed.

       DESTROY
	   When	the object goes	out of scope, the destructor is	called.	This
	   destructor will attempt to unlink the file (using unlink1) if the
	   constructor was called with UNLINK set to 1 (the default state if
	   UNLINK is not specified).

	   No error is given if	the unlink fails.

	   If the object has been passed to a child process during a fork, the
	   file	will be	deleted	when the object	goes out of scope in the
	   parent.

	   For a temporary directory object the	directory will be removed
	   unless the CLEANUP argument was used	in the constructor (and	set to
	   false) or "unlink_on_destroy" was modified after creation.  Note
	   that	if a temp directory is your current directory, it cannot be
	   removed - a warning will be given in	this case.  "chdir()" out of
	   the directory before	letting	the object go out of scope.

	   If the global variable $KEEP_ALL is true, the file or directory
	   will	not be removed.

FUNCTIONS
       This section describes the recommended interface	for generating
       temporary files and directories.

       tempfile
	   This	is the basic function to generate temporary files.  The
	   behaviour of	the file can be	changed	using various options:

	     $fh = tempfile();
	     ($fh, $filename) =	tempfile();

	   Create a temporary file in  the directory specified for temporary
	   files, as specified by the tmpdir() function	in File::Spec.

	     ($fh, $filename) =	tempfile($template);

	   Create a temporary file in the current directory using the supplied
	   template.  Trailing `X' characters are replaced with	random letters
	   to generate the filename.  At least four `X'	characters must	be
	   present at the end of the template.

	     ($fh, $filename) =	tempfile($template, SUFFIX => $suffix)

	   Same	as previously, except that a suffix is added to	the template
	   after the `X' translation.  Useful for ensuring that	a temporary
	   filename has	a particular extension when needed by other
	   applications.  But see the WARNING at the end.

	     ($fh, $filename) =	tempfile($template, DIR	=> $dir);

	   Translates the template as before except that a directory name is
	   specified.

	     ($fh, $filename) =	tempfile($template, TMPDIR => 1);

	   Equivalent to specifying a DIR of "File::Spec->tmpdir", writing the
	   file	into the same temporary	directory as would be used if no
	   template was	specified at all.

	     ($fh, $filename) =	tempfile($template, UNLINK => 1);

	   Return the filename and filehandle as before	except that the	file
	   is automatically removed when the program exits (dependent on
	   $KEEP_ALL). Default is for the file to be removed if	a file handle
	   is requested	and to be kept if the filename is requested. In	a
	   scalar context (where no filename is	returned) the file is always
	   deleted either (depending on	the operating system) on exit or when
	   it is closed	(unless	$KEEP_ALL is true when the temp	file is
	   created).

	   Use the object-oriented interface if	fine-grained control of	when a
	   file	is removed is required.

	   If the template is not specified, a template	is always
	   automatically generated. This temporary file	is placed in tmpdir()
	   (File::Spec)	unless a directory is specified	explicitly with	the
	   DIR option.

	     $fh = tempfile( DIR => $dir );

	   If called in	scalar context,	only the filehandle is returned	and
	   the file will automatically be deleted when closed on operating
	   systems that	support	this (see the description of tmpfile()
	   elsewhere in	this document).	 This is the preferred mode of
	   operation, as if you	only have a filehandle,	you can	never create a
	   race	condition by fumbling with the filename. On systems that can
	   not unlink an open file or can not mark a file as temporary when it
	   is opened (for example, Windows NT uses the "O_TEMPORARY" flag) the
	   file	is marked for deletion when the	program	ends (equivalent to
	   setting UNLINK to 1). The "UNLINK" flag is ignored if present.

	     (undef, $filename)	= tempfile($template, OPEN => 0);

	   This	will return the	filename based on the template but will	not
	   open	this file.  Cannot be used in conjunction with UNLINK set to
	   true. Default is to always open the file to protect from possible
	   race	conditions. A warning is issued	if warnings are	turned on.
	   Consider using the tmpnam() and mktemp() functions described
	   elsewhere in	this document if opening the file is not required.

	   If the operating system supports it (for example BSD	derived
	   systems), the filehandle will be opened with	O_EXLOCK (open with
	   exclusive file lock).  This can sometimes cause problems if the
	   intention is	to pass	the filename to	another	system that expects to
	   take	an exclusive lock itself (such as DBD::SQLite) whilst ensuring
	   that	the tempfile is	not reused. In this situation the "EXLOCK"
	   option can be passed	to tempfile. By	default	EXLOCK will be true
	   (this retains compatibility with earlier releases).

	     ($fh, $filename) =	tempfile($template, EXLOCK => 0);

	   Options can be combined as required.

	   Will	croak()	if there is an error.

       tempdir
	   This	is the recommended interface for creation of temporary
	   directories.	 By default the	directory will not be removed on exit
	   (that is, it	won't be temporary; this behaviour can not be changed
	   because of issues with backwards compatibility). To enable removal
	   either use the CLEANUP option which will trigger removal on program
	   exit, or consider using the "newdir"	method in the object interface
	   which will allow the	directory to be	cleaned	up when	the object
	   goes	out of scope.

	   The behaviour of the	function depends on the	arguments:

	     $tempdir =	tempdir();

	   Create a directory in tmpdir() (see File::Spec).

	     $tempdir =	tempdir( $template );

	   Create a directory from the supplied	template. This template	is
	   similar to that described for tempfile(). `X' characters at the end
	   of the template are replaced	with random letters to construct the
	   directory name. At least four `X' characters	must be	in the
	   template.

	     $tempdir =	tempdir	( DIR => $dir );

	   Specifies the directory to use for the temporary directory.	The
	   temporary directory name is derived from an internal	template.

	     $tempdir =	tempdir	( $template, DIR => $dir );

	   Prepend the supplied	directory name to the template.	The template
	   should not include parent directory specifications itself. Any
	   parent directory specifications are removed from the	template
	   before prepending the supplied directory.

	     $tempdir =	tempdir	( $template, TMPDIR => 1 );

	   Using the supplied template,	create the temporary directory in a
	   standard location for temporary files. Equivalent to	doing

	     $tempdir =	tempdir	( $template, DIR => File::Spec->tmpdir);

	   but shorter.	Parent directory specifications	are stripped from the
	   template itself. The	"TMPDIR" option	is ignored if "DIR" is set
	   explicitly.	Additionally, "TMPDIR" is implied if neither a
	   template nor	a directory are	supplied.

	     $tempdir =	tempdir( $template, CLEANUP => 1);

	   Create a temporary directory	using the supplied template, but
	   attempt to remove it	(and all files inside it) when the program
	   exits. Note that an attempt will be made to remove all files	from
	   the directory even if they were not created by this module
	   (otherwise why ask to clean it up?).	The directory removal is made
	   with	the rmtree() function from the File::Path module.  Of course,
	   if the template is not specified, the temporary directory will be
	   created in tmpdir() and will	also be	removed	at program exit.

	   Will	croak()	if there is an error.

MKTEMP FUNCTIONS
       The following functions are Perl	implementations	of the mktemp()	family
       of temp file generation system calls.

       mkstemp
	   Given a template, returns a filehandle to the temporary file	and
	   the name of the file.

	     ($fh, $name) = mkstemp( $template );

	   In scalar context, just the filehandle is returned.

	   The template	may be any filename with some number of	X's appended
	   to it, for example /tmp/temp.XXXX. The trailing X's are replaced
	   with	unique alphanumeric combinations.

	   Will	croak()	if there is an error.

       mkstemps
	   Similar to mkstemp(), except	that an	extra argument can be supplied
	   with	a suffix to be appended	to the template.

	     ($fh, $name) = mkstemps( $template, $suffix );

	   For example a template of "testXXXXXX" and suffix of	".dat" would
	   generate a file similar to testhGji_w.dat.

	   Returns just	the filehandle alone when called in scalar context.

	   Will	croak()	if there is an error.

       mkdtemp
	   Create a directory from a template. The template must end in	X's
	   that	are replaced by	the routine.

	     $tmpdir_name = mkdtemp($template);

	   Returns the name of the temporary directory created.

	   Directory must be removed by	the caller.

	   Will	croak()	if there is an error.

       mktemp
	   Returns a valid temporary filename but does not guarantee that the
	   file	will not be opened by someone else.

	     $unopened_file = mktemp($template);

	   Template is the same	as that	required by mkstemp().

	   Will	croak()	if there is an error.

POSIX FUNCTIONS
       This section describes the re-implementation of the tmpnam() and
       tmpfile() functions described in	POSIX using the	mkstemp() from this
       module.

       Unlike the POSIX	implementations, the directory used for	the temporary
       file is not specified in	a system include file ("P_tmpdir") but simply
       depends on the choice of	tmpdir() returned by File::Spec. On some
       implementations this location can be set	using the "TMPDIR" environment
       variable, which may not be secure.  If this is a	problem, simply	use
       mkstemp() and specify a template.

       tmpnam
	   When	called in scalar context, returns the full name	(including
	   path) of a temporary	file (uses mktemp()). The only check is	that
	   the file does not already exist, but	there is no guarantee that
	   that	condition will continue	to apply.

	     $file = tmpnam();

	   When	called in list context,	a filehandle to	the open file and a
	   filename are	returned. This is achieved by calling mkstemp()	after
	   constructing	a suitable template.

	     ($fh, $file) = tmpnam();

	   If possible,	this form should be used to prevent possible race
	   conditions.

	   See "tmpdir"	in File::Spec for information on the choice of
	   temporary directory for a particular	operating system.

	   Will	croak()	if there is an error.

       tmpfile
	   Returns the filehandle of a temporary file.

	     $fh = tmpfile();

	   The file is removed when the	filehandle is closed or	when the
	   program exits. No access to the filename is provided.

	   If the temporary file can not be created undef is returned.
	   Currently this command will probably	not work when the temporary
	   directory is	on an NFS file system.

	   Will	croak()	if there is an error.

ADDITIONAL FUNCTIONS
       These functions are provided for	backwards compatibility	with common
       tempfile	generation C library functions.

       They are	not exported and must be addressed using the full package
       name.

       tempnam
	   Return the name of a	temporary file in the specified	directory
	   using a prefix. The file is guaranteed not to exist at the time the
	   function was	called,	but such guarantees are	good for one clock
	   tick	only.  Always use the proper form of "sysopen" with "O_CREAT |
	   O_EXCL" if you must open such a filename.

	     $filename = File::Temp::tempnam( $dir, $prefix );

	   Equivalent to running mktemp() with $dir/$prefixXXXXXXXX (using
	   unix	file convention	as an example)

	   Because this	function uses mktemp(),	it can suffer from race
	   conditions.

	   Will	croak()	if there is an error.

UTILITY	FUNCTIONS
       Useful functions	for dealing with the filehandle	and filename.

       unlink0
	   Given an open filehandle and	the associated filename, make a	safe
	   unlink. This	is achieved by first checking that the filename	and
	   filehandle initially	point to the same file and that	the number of
	   links to the	file is	1 (all fields returned by stat() are
	   compared).  Then the	filename is unlinked and the filehandle
	   checked once	again to verify	that the number	of links on that file
	   is now 0.  This is the closest you can come to making sure that the
	   filename unlinked was the same as the file whose descriptor you
	   hold.

	     unlink0($fh, $path)
		or die "Error unlinking	file $path safely";

	   Returns false on error but croaks() if there	is a security anomaly.
	   The filehandle is not closed	since on some occasions	this is	not
	   required.

	   On some platforms, for example Windows NT, it is not	possible to
	   unlink an open file (the file must be closed	first).	On those
	   platforms, the actual unlinking is deferred until the program ends
	   and good status is returned.	A check	is still performed to make
	   sure	that the filehandle and	filename are pointing to the same
	   thing (but not at the time the end block is executed	since the
	   deferred removal may	not have access	to the filehandle).

	   Additionally, on Windows NT not all the fields returned by stat()
	   can be compared. For	example, the "dev" and "rdev" fields seem to
	   be different.  Also,	it seems that the size of the file returned by
	   stat() does not always agree, with "stat(FH)" being more accurate
	   than	"stat(filename)", presumably because of	caching	issues even
	   when	using autoflush	(this is usually overcome by waiting a while
	   after writing to the	tempfile before	attempting to "unlink0"	it).

	   Finally, on NFS file	systems	the link count of the file handle does
	   not always go to zero immediately after unlinking. Currently, this
	   command is expected to fail on NFS disks.

	   This	function is disabled if	the global variable $KEEP_ALL is true
	   and an unlink on open file is supported. If the unlink is to	be
	   deferred to the END block, the file is still	registered for
	   removal.

	   This	function should	not be called if you are using the object
	   oriented interface since the	it will	interfere with the object
	   destructor deleting the file.

       cmpstat
	   Compare "stat" of filehandle	with "stat" of provided	filename.
	   This	can be used to check that the filename and filehandle
	   initially point to the same file and	that the number	of links to
	   the file is 1 (all fields returned by stat()	are compared).

	     cmpstat($fh, $path)
		or die "Error comparing	handle with file";

	   Returns false if the	stat information differs or if the link	count
	   is greater than 1. Calls croak if there is a	security anomaly.

	   On certain platforms, for example Windows, not all the fields
	   returned by stat() can be compared. For example, the	"dev" and
	   "rdev" fields seem to be different in Windows.  Also, it seems that
	   the size of the file	returned by stat() does	not always agree, with
	   "stat(FH)" being more accurate than "stat(filename)", presumably
	   because of caching issues even when using autoflush (this is
	   usually overcome by waiting a while after writing to	the tempfile
	   before attempting to	"unlink0" it).

	   Not exported	by default.

       unlink1
	   Similar to "unlink0"	except after file comparison using cmpstat,
	   the filehandle is closed prior to attempting	to unlink the file.
	   This	allows the file	to be removed without using an END block, but
	   does	mean that the post-unlink comparison of	the filehandle state
	   provided by "unlink0" is not	available.

	     unlink1($fh, $path)
		or die "Error closing and unlinking file";

	   Usually called from the object destructor when using	the OO
	   interface.

	   Not exported	by default.

	   This	function is disabled if	the global variable $KEEP_ALL is true.

	   Can call croak() if there is	a security anomaly during the stat()
	   comparison.

       cleanup
	   Calling this	function will cause any	temp files or temp directories
	   that	are registered for removal to be removed. This happens
	   automatically when the process exits	but can	be triggered manually
	   if the caller is sure that none of the temp files are required.
	   This	method can be registered as an Apache callback.

	   Note	that if	a temp directory is your current directory, it cannot
	   be removed.	"chdir()" out of the directory first before calling
	   "cleanup()".	(For the cleanup at program exit when the CLEANUP flag
	   is set, this	happens	automatically.)

	   On OSes where temp files are	automatically removed when the temp
	   file	is closed, calling this	function will have no effect other
	   than	to remove temporary directories	(which may include temporary
	   files).

	     File::Temp::cleanup();

	   Not exported	by default.

PACKAGE	VARIABLES
       These functions control the global state	of the package.

       safe_level
	   Controls the	lengths	to which the module will go to check the
	   safety of the temporary file	or directory before proceeding.
	   Options are:

	   STANDARD
		   Do the basic	security measures to ensure the	directory
		   exists and is writable, that	temporary files	are opened
		   only	if they	do not already exist, and that possible	race
		   conditions are avoided.  Finally the	unlink0	function is
		   used	to remove files	safely.

	   MEDIUM  In addition to the STANDARD security, the output directory
		   is checked to make sure that	it is owned either by root or
		   the user running the	program. If the	directory is writable
		   by group or by other, it is then checked to make sure that
		   the sticky bit is set.

		   Will	not work on platforms that do not support the "-k"
		   test	for sticky bit.

	   HIGH	   In addition to the MEDIUM security checks, also check for
		   the possibility of ``chown()	giveaway'' using the POSIX
		   sysconf() function. If this is a possibility, each
		   directory in	the path is checked in turn for	safeness,
		   recursively walking back to the root	directory.

		   For platforms that do not support the POSIX
		   "_PC_CHOWN_RESTRICTED" symbol (for example, Windows NT) it
		   is assumed that ``chown() giveaway''	is possible and	the
		   recursive test is performed.

	   The level can be changed as follows:

	     File::Temp->safe_level( File::Temp::HIGH );

	   The level constants are not exported	by the module.

	   Currently, you must be running at least perl	v5.6.0 in order	to run
	   with	MEDIUM or HIGH security. This is simply	because	the safety
	   tests use functions from Fcntl that are not available in older
	   versions of perl. The problem is that the version number for	Fcntl
	   is the same in perl 5.6.0 and in 5.005_03 even though they are
	   different versions.

	   On systems that do not support the HIGH or MEDIUM safety levels
	   (for	example	Win NT or OS/2)	any attempt to change the level	will
	   be ignored. The decision to ignore rather than raise	an exception
	   allows portable programs to be written with high security in	mind
	   for the systems that	can support this without those programs
	   failing on systems where the	extra tests are	irrelevant.

	   If you really need to see whether the change	has been accepted
	   simply examine the return value of "safe_level".

	     $newlevel = File::Temp->safe_level( File::Temp::HIGH );
	     die "Could	not change to high security"
		 if $newlevel != File::Temp::HIGH;

       TopSystemUID
	   This	is the highest UID on the current system that refers to	a root
	   UID.	This is	used to	make sure that the temporary directory is
	   owned by a system UID ("root", "bin", "sys" etc) rather than	simply
	   by root.

	   This	is required since on many unix systems "/tmp" is not owned by
	   root.

	   Default is to assume	that any UID less than or equal	to 10 is a
	   root	UID.

	     File::Temp->top_system_uid(10);
	     my	$topid = File::Temp->top_system_uid;

	   This	value can be adjusted to reduce	security checking if required.
	   The value is	only relevant when "safe_level"	is set to MEDIUM or
	   higher.

       $KEEP_ALL
	   Controls whether temporary files and	directories should be retained
	   regardless of any instructions in the program to remove them
	   automatically.  This	is useful for debugging	but should not be used
	   in production code.

	     $File::Temp::KEEP_ALL = 1;

	   Default is for files	to be removed as requested by the caller.

	   In some cases, files	will only be retained if this variable is true
	   when	the file is created. This means	that you can not create	a
	   temporary file, set this variable and expect	the temp file to still
	   be around when the program exits.

       $DEBUG
	   Controls whether debugging messages should be enabled.

	     $File::Temp::DEBUG	= 1;

	   Default is for debugging mode to be disabled.

WARNING
       For maximum security, endeavour always to avoid ever looking at,
       touching, or even imputing the existence	of the filename.  You do not
       know that that filename is connected to the same	file as	the handle you
       have, and attempts to check this	can only trigger more race conditions.
       It's far	more secure to use the filehandle alone	and dispense with the
       filename	altogether.

       If you need to pass the handle to something that	expects	a filename
       then on a unix system you can use ""/dev/fd/" . fileno($fh)" for
       arbitrary programs. Perl	code that uses the 2-argument version of
       "open" can be passed ""+<=&" . fileno($fh)". Otherwise you will need to
       pass the	filename. You will have	to clear the close-on-exec bit on that
       file descriptor before passing it to another process.

	   use Fcntl qw/F_SETFD	F_GETFD/;
	   fcntl($tmpfh, F_SETFD, 0)
	       or die "Can't clear close-on-exec flag on temp fh: $!\n";

   Temporary files and NFS
       Some problems are associated with using temporary files that reside on
       NFS file	systems	and it is recommended that a local filesystem is used
       whenever	possible. Some of the security tests will most probably	fail
       when the	temp file is not local.	Additionally, be aware that the
       performance of I/O operations over NFS will not be as good as for a
       local disk.

   Forking
       In some cases files created by File::Temp are removed from within an
       END block. Since	END blocks are triggered when a	child process exits
       (unless "POSIX::_exit()"	is used	by the child) File::Temp takes care to
       only remove those temp files created by a particular process ID.	This
       means that a child will not attempt to remove temp files	created	by the
       parent process.

       If you are forking many processes in parallel that are all creating
       temporary files,	you may	need to	reset the random number	seed using
       srand(EXPR) in each child else all the children will attempt to walk
       through the same	set of random file names and may well cause themselves
       to give up if they exceed the number of retry attempts.

   Directory removal
       Note that if you	have chdir'ed into the temporary directory and it is
       subsequently cleaned up (either in the END block	or as part of object
       destruction), then you will get a warning from File::Path::rmtree().

   Taint mode
       If you need to run code under taint mode, updating to the latest
       File::Spec is highly recommended.

   BINMODE
       The file	returned by File::Temp will have been opened in	binary mode if
       such a mode is available. If that is not	correct, use the "binmode()"
       function	to change the mode of the filehandle.

       Note that you can modify	the encoding of	a file opened by File::Temp
       also by using "binmode()".

HISTORY
       Originally began	life in	May 1999 as an XS interface to the system
       mkstemp() function. In March 2000, the OpenBSD mkstemp()	code was
       translated to Perl for total control of the code's security checking,
       to ensure the presence of the function regardless of operating system
       and to help with	portability. The module	was shipped as a standard part
       of perl from v5.6.1.

       Thanks to Tom Christiansen for suggesting that this module should be
       written and providing ideas for code improvements and security
       enhancements.

SEE ALSO
       "tmpnam"	in POSIX, "tmpfile" in POSIX, File::Spec, File::Path

       See IO::File and	File::MkTemp, Apache::TempFile for different
       implementations of temporary file handling.

       See File::Tempdir for an	alternative object-oriented wrapper for	the
       "tempdir" function.

       # vim: ts=2 sts=2 sw=2 et:

SUPPORT
   Bugs	/ Feature Requests
       Please report any bugs or feature requests through the issue tracker at
       <http://rt.cpan.org/Public/Dist/Display.html?Name=File-Temp>.  You will
       be notified automatically of any	progress on your issue.

   Source Code
       This is open source software.  The code repository is available for
       public review and contribution under the	terms of the license.

       <https://github.com/Perl-Toolchain-Gang/File-Temp>

	 git clone https://github.com/Perl-Toolchain-Gang/File-Temp.git

AUTHOR
       Tim Jenness <tjenness@cpan.org>

CONTRIBUTORS
       o   Ben Tilly <btilly@gmail.com>

       o   David Golden	<dagolden@cpan.org>

       o   David Steinbrunner <dsteinbrunner@pobox.com>

       o   Ed Avis <eda@linux01.wcl.local>

       o   James E. Keenan <jkeen@verizon.net>

       o   Karen Etheridge <ether@cpan.org>

       o   Kevin Ryde <user42@zip.com.au>

       o   Olivier Mengue <dolmen@cpan.org>

       o   Peter John Acklam <pjacklam@online.no>

       o   Peter Rabbitson <ribasushi@cpan.org>

COPYRIGHT AND LICENSE
       This software is	copyright (c) 2013 by Tim Jenness and the UK Particle
       Physics and Astronomy Research Council.

       This is free software; you can redistribute it and/or modify it under
       the same	terms as the Perl 5 programming	language system	itself.

perl v5.26.0			  2017-04-19			 File::Temp(3)

NAME | VERSION | SYNOPSIS | DESCRIPTION | OBJECT-ORIENTED INTERFACE | FUNCTIONS | MKTEMP FUNCTIONS | POSIX FUNCTIONS | ADDITIONAL FUNCTIONS | UTILITY FUNCTIONS | PACKAGE VARIABLES | WARNING | HISTORY | SEE ALSO | SUPPORT | AUTHOR | CONTRIBUTORS | COPYRIGHT AND LICENSE

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