1File::Temp(3) User Contributed Perl Documentation File::Temp(3)
2
3
4
6 File::Temp - return name and handle of a temporary file safely
7
9 version 0.2301
10
12 use File::Temp qw/ tempfile tempdir /;
13
14 $fh = tempfile();
15 ($fh, $filename) = tempfile();
16
17 ($fh, $filename) = tempfile( $template, DIR => $dir);
18 ($fh, $filename) = tempfile( $template, SUFFIX => '.dat');
19 ($fh, $filename) = tempfile( $template, TMPDIR => 1 );
20
21 binmode( $fh, ":utf8" );
22
23 $dir = tempdir( CLEANUP => 1 );
24 ($fh, $filename) = tempfile( DIR => $dir );
25
26 Object interface:
27
28 require File::Temp;
29 use File::Temp ();
30 use File::Temp qw/ :seekable /;
31
32 $fh = File::Temp->new();
33 $fname = $fh->filename;
34
35 $fh = File::Temp->new(TEMPLATE => $template);
36 $fname = $fh->filename;
37
38 $tmp = File::Temp->new( UNLINK => 0, SUFFIX => '.dat' );
39 print $tmp "Some data\n";
40 print "Filename is $tmp\n";
41 $tmp->seek( 0, SEEK_END );
42
43 The following interfaces are provided for compatibility with existing
44 APIs. They should not be used in new code.
45
46 MkTemp family:
47
48 use File::Temp qw/ :mktemp /;
49
50 ($fh, $file) = mkstemp( "tmpfileXXXXX" );
51 ($fh, $file) = mkstemps( "tmpfileXXXXXX", $suffix);
52
53 $tmpdir = mkdtemp( $template );
54
55 $unopened_file = mktemp( $template );
56
57 POSIX functions:
58
59 use File::Temp qw/ :POSIX /;
60
61 $file = tmpnam();
62 $fh = tmpfile();
63
64 ($fh, $file) = tmpnam();
65
66 Compatibility functions:
67
68 $unopened_file = File::Temp::tempnam( $dir, $pfx );
69
71 "File::Temp" can be used to create and open temporary files in a safe
72 way. There is both a function interface and an object-oriented
73 interface. The File::Temp constructor or the tempfile() function can
74 be used to return the name and the open filehandle of a temporary file.
75 The tempdir() function can be used to create a temporary directory.
76
77 The security aspect of temporary file creation is emphasized such that
78 a filehandle and filename are returned together. This helps guarantee
79 that a race condition can not occur where the temporary file is created
80 by another process between checking for the existence of the file and
81 its opening. Additional security levels are provided to check, for
82 example, that the sticky bit is set on world writable directories. See
83 "safe_level" for more information.
84
85 For compatibility with popular C library functions, Perl
86 implementations of the mkstemp() family of functions are provided.
87 These are, mkstemp(), mkstemps(), mkdtemp() and mktemp().
88
89 Additionally, implementations of the standard POSIX tmpnam() and
90 tmpfile() functions are provided if required.
91
92 Implementations of mktemp(), tmpnam(), and tempnam() are provided, but
93 should be used with caution since they return only a filename that was
94 valid when function was called, so cannot guarantee that the file will
95 not exist by the time the caller opens the filename.
96
97 Filehandles returned by these functions support the seekable methods.
98
100 This is the primary interface for interacting with "File::Temp". Using
101 the OO interface a temporary file can be created when the object is
102 constructed and the file can be removed when the object is no longer
103 required.
104
105 Note that there is no method to obtain the filehandle from the
106 "File::Temp" object. The object itself acts as a filehandle. The
107 object isa "IO::Handle" and isa "IO::Seekable" so all those methods are
108 available.
109
110 Also, the object is configured such that it stringifies to the name of
111 the temporary file and so can be compared to a filename directly. It
112 numifies to the "refaddr" the same as other handles and so can be
113 compared to other handles with "==".
114
115 $fh eq $filename # as a string
116 $fh != \*STDOUT # as a number
117
118 new Create a temporary file object.
119
120 my $tmp = File::Temp->new();
121
122 by default the object is constructed as if "tempfile" was called
123 without options, but with the additional behaviour that the
124 temporary file is removed by the object destructor if UNLINK is set
125 to true (the default).
126
127 Supported arguments are the same as for "tempfile": UNLINK
128 (defaulting to true), DIR, EXLOCK and SUFFIX. Additionally, the
129 filename template is specified using the TEMPLATE option. The OPEN
130 option is not supported (the file is always opened).
131
132 $tmp = File::Temp->new( TEMPLATE => 'tempXXXXX',
133 DIR => 'mydir',
134 SUFFIX => '.dat');
135
136 Arguments are case insensitive.
137
138 Can call croak() if an error occurs.
139
140 newdir
141 Create a temporary directory using an object oriented interface.
142
143 $dir = File::Temp->newdir();
144
145 By default the directory is deleted when the object goes out of
146 scope.
147
148 Supports the same options as the "tempdir" function. Note that
149 directories created with this method default to CLEANUP => 1.
150
151 $dir = File::Temp->newdir( $template, %options );
152
153 A template may be specified either with a leading template or with
154 a TEMPLATE argument.
155
156 filename
157 Return the name of the temporary file associated with this object
158 (if the object was created using the "new" constructor).
159
160 $filename = $tmp->filename;
161
162 This method is called automatically when the object is used as a
163 string.
164
165 dirname
166 Return the name of the temporary directory associated with this
167 object (if the object was created using the "newdir" constructor).
168
169 $dirname = $tmpdir->dirname;
170
171 This method is called automatically when the object is used in
172 string context.
173
174 unlink_on_destroy
175 Control whether the file is unlinked when the object goes out of
176 scope. The file is removed if this value is true and $KEEP_ALL is
177 not.
178
179 $fh->unlink_on_destroy( 1 );
180
181 Default is for the file to be removed.
182
183 DESTROY
184 When the object goes out of scope, the destructor is called. This
185 destructor will attempt to unlink the file (using unlink1) if the
186 constructor was called with UNLINK set to 1 (the default state if
187 UNLINK is not specified).
188
189 No error is given if the unlink fails.
190
191 If the object has been passed to a child process during a fork, the
192 file will be deleted when the object goes out of scope in the
193 parent.
194
195 For a temporary directory object the directory will be removed
196 unless the CLEANUP argument was used in the constructor (and set to
197 false) or "unlink_on_destroy" was modified after creation. Note
198 that if a temp directory is your current directory, it cannot be
199 removed - a warning will be given in this case. "chdir()" out of
200 the directory before letting the object go out of scope.
201
202 If the global variable $KEEP_ALL is true, the file or directory
203 will not be removed.
204
206 This section describes the recommended interface for generating
207 temporary files and directories.
208
209 tempfile
210 This is the basic function to generate temporary files. The
211 behaviour of the file can be changed using various options:
212
213 $fh = tempfile();
214 ($fh, $filename) = tempfile();
215
216 Create a temporary file in the directory specified for temporary
217 files, as specified by the tmpdir() function in File::Spec.
218
219 ($fh, $filename) = tempfile($template);
220
221 Create a temporary file in the current directory using the supplied
222 template. Trailing `X' characters are replaced with random letters
223 to generate the filename. At least four `X' characters must be
224 present at the end of the template.
225
226 ($fh, $filename) = tempfile($template, SUFFIX => $suffix)
227
228 Same as previously, except that a suffix is added to the template
229 after the `X' translation. Useful for ensuring that a temporary
230 filename has a particular extension when needed by other
231 applications. But see the WARNING at the end.
232
233 ($fh, $filename) = tempfile($template, DIR => $dir);
234
235 Translates the template as before except that a directory name is
236 specified.
237
238 ($fh, $filename) = tempfile($template, TMPDIR => 1);
239
240 Equivalent to specifying a DIR of "File::Spec->tmpdir", writing the
241 file into the same temporary directory as would be used if no
242 template was specified at all.
243
244 ($fh, $filename) = tempfile($template, UNLINK => 1);
245
246 Return the filename and filehandle as before except that the file
247 is automatically removed when the program exits (dependent on
248 $KEEP_ALL). Default is for the file to be removed if a file handle
249 is requested and to be kept if the filename is requested. In a
250 scalar context (where no filename is returned) the file is always
251 deleted either (depending on the operating system) on exit or when
252 it is closed (unless $KEEP_ALL is true when the temp file is
253 created).
254
255 Use the object-oriented interface if fine-grained control of when a
256 file is removed is required.
257
258 If the template is not specified, a template is always
259 automatically generated. This temporary file is placed in tmpdir()
260 (File::Spec) unless a directory is specified explicitly with the
261 DIR option.
262
263 $fh = tempfile( DIR => $dir );
264
265 If called in scalar context, only the filehandle is returned and
266 the file will automatically be deleted when closed on operating
267 systems that support this (see the description of tmpfile()
268 elsewhere in this document). This is the preferred mode of
269 operation, as if you only have a filehandle, you can never create a
270 race condition by fumbling with the filename. On systems that can
271 not unlink an open file or can not mark a file as temporary when it
272 is opened (for example, Windows NT uses the "O_TEMPORARY" flag) the
273 file is marked for deletion when the program ends (equivalent to
274 setting UNLINK to 1). The "UNLINK" flag is ignored if present.
275
276 (undef, $filename) = tempfile($template, OPEN => 0);
277
278 This will return the filename based on the template but will not
279 open this file. Cannot be used in conjunction with UNLINK set to
280 true. Default is to always open the file to protect from possible
281 race conditions. A warning is issued if warnings are turned on.
282 Consider using the tmpnam() and mktemp() functions described
283 elsewhere in this document if opening the file is not required.
284
285 If the operating system supports it (for example BSD derived
286 systems), the filehandle will be opened with O_EXLOCK (open with
287 exclusive file lock). This can sometimes cause problems if the
288 intention is to pass the filename to another system that expects to
289 take an exclusive lock itself (such as DBD::SQLite) whilst ensuring
290 that the tempfile is not reused. In this situation the "EXLOCK"
291 option can be passed to tempfile. By default EXLOCK will be true
292 (this retains compatibility with earlier releases).
293
294 ($fh, $filename) = tempfile($template, EXLOCK => 0);
295
296 Options can be combined as required.
297
298 Will croak() if there is an error.
299
300 tempdir
301 This is the recommended interface for creation of temporary
302 directories. By default the directory will not be removed on exit
303 (that is, it won't be temporary; this behaviour can not be changed
304 because of issues with backwards compatibility). To enable removal
305 either use the CLEANUP option which will trigger removal on program
306 exit, or consider using the "newdir" method in the object interface
307 which will allow the directory to be cleaned up when the object
308 goes out of scope.
309
310 The behaviour of the function depends on the arguments:
311
312 $tempdir = tempdir();
313
314 Create a directory in tmpdir() (see File::Spec).
315
316 $tempdir = tempdir( $template );
317
318 Create a directory from the supplied template. This template is
319 similar to that described for tempfile(). `X' characters at the end
320 of the template are replaced with random letters to construct the
321 directory name. At least four `X' characters must be in the
322 template.
323
324 $tempdir = tempdir ( DIR => $dir );
325
326 Specifies the directory to use for the temporary directory. The
327 temporary directory name is derived from an internal template.
328
329 $tempdir = tempdir ( $template, DIR => $dir );
330
331 Prepend the supplied directory name to the template. The template
332 should not include parent directory specifications itself. Any
333 parent directory specifications are removed from the template
334 before prepending the supplied directory.
335
336 $tempdir = tempdir ( $template, TMPDIR => 1 );
337
338 Using the supplied template, create the temporary directory in a
339 standard location for temporary files. Equivalent to doing
340
341 $tempdir = tempdir ( $template, DIR => File::Spec->tmpdir);
342
343 but shorter. Parent directory specifications are stripped from the
344 template itself. The "TMPDIR" option is ignored if "DIR" is set
345 explicitly. Additionally, "TMPDIR" is implied if neither a
346 template nor a directory are supplied.
347
348 $tempdir = tempdir( $template, CLEANUP => 1);
349
350 Create a temporary directory using the supplied template, but
351 attempt to remove it (and all files inside it) when the program
352 exits. Note that an attempt will be made to remove all files from
353 the directory even if they were not created by this module
354 (otherwise why ask to clean it up?). The directory removal is made
355 with the rmtree() function from the File::Path module. Of course,
356 if the template is not specified, the temporary directory will be
357 created in tmpdir() and will also be removed at program exit.
358
359 Will croak() if there is an error.
360
362 The following functions are Perl implementations of the mktemp() family
363 of temp file generation system calls.
364
365 mkstemp
366 Given a template, returns a filehandle to the temporary file and
367 the name of the file.
368
369 ($fh, $name) = mkstemp( $template );
370
371 In scalar context, just the filehandle is returned.
372
373 The template may be any filename with some number of X's appended
374 to it, for example /tmp/temp.XXXX. The trailing X's are replaced
375 with unique alphanumeric combinations.
376
377 Will croak() if there is an error.
378
379 mkstemps
380 Similar to mkstemp(), except that an extra argument can be supplied
381 with a suffix to be appended to the template.
382
383 ($fh, $name) = mkstemps( $template, $suffix );
384
385 For example a template of "testXXXXXX" and suffix of ".dat" would
386 generate a file similar to testhGji_w.dat.
387
388 Returns just the filehandle alone when called in scalar context.
389
390 Will croak() if there is an error.
391
392 mkdtemp
393 Create a directory from a template. The template must end in X's
394 that are replaced by the routine.
395
396 $tmpdir_name = mkdtemp($template);
397
398 Returns the name of the temporary directory created.
399
400 Directory must be removed by the caller.
401
402 Will croak() if there is an error.
403
404 mktemp
405 Returns a valid temporary filename but does not guarantee that the
406 file will not be opened by someone else.
407
408 $unopened_file = mktemp($template);
409
410 Template is the same as that required by mkstemp().
411
412 Will croak() if there is an error.
413
415 This section describes the re-implementation of the tmpnam() and
416 tmpfile() functions described in POSIX using the mkstemp() from this
417 module.
418
419 Unlike the POSIX implementations, the directory used for the temporary
420 file is not specified in a system include file ("P_tmpdir") but simply
421 depends on the choice of tmpdir() returned by File::Spec. On some
422 implementations this location can be set using the "TMPDIR" environment
423 variable, which may not be secure. If this is a problem, simply use
424 mkstemp() and specify a template.
425
426 tmpnam
427 When called in scalar context, returns the full name (including
428 path) of a temporary file (uses mktemp()). The only check is that
429 the file does not already exist, but there is no guarantee that
430 that condition will continue to apply.
431
432 $file = tmpnam();
433
434 When called in list context, a filehandle to the open file and a
435 filename are returned. This is achieved by calling mkstemp() after
436 constructing a suitable template.
437
438 ($fh, $file) = tmpnam();
439
440 If possible, this form should be used to prevent possible race
441 conditions.
442
443 See "tmpdir" in File::Spec for information on the choice of
444 temporary directory for a particular operating system.
445
446 Will croak() if there is an error.
447
448 tmpfile
449 Returns the filehandle of a temporary file.
450
451 $fh = tmpfile();
452
453 The file is removed when the filehandle is closed or when the
454 program exits. No access to the filename is provided.
455
456 If the temporary file can not be created undef is returned.
457 Currently this command will probably not work when the temporary
458 directory is on an NFS file system.
459
460 Will croak() if there is an error.
461
463 These functions are provided for backwards compatibility with common
464 tempfile generation C library functions.
465
466 They are not exported and must be addressed using the full package
467 name.
468
469 tempnam
470 Return the name of a temporary file in the specified directory
471 using a prefix. The file is guaranteed not to exist at the time the
472 function was called, but such guarantees are good for one clock
473 tick only. Always use the proper form of "sysopen" with "O_CREAT |
474 O_EXCL" if you must open such a filename.
475
476 $filename = File::Temp::tempnam( $dir, $prefix );
477
478 Equivalent to running mktemp() with $dir/$prefixXXXXXXXX (using
479 unix file convention as an example)
480
481 Because this function uses mktemp(), it can suffer from race
482 conditions.
483
484 Will croak() if there is an error.
485
487 Useful functions for dealing with the filehandle and filename.
488
489 unlink0
490 Given an open filehandle and the associated filename, make a safe
491 unlink. This is achieved by first checking that the filename and
492 filehandle initially point to the same file and that the number of
493 links to the file is 1 (all fields returned by stat() are
494 compared). Then the filename is unlinked and the filehandle
495 checked once again to verify that the number of links on that file
496 is now 0. This is the closest you can come to making sure that the
497 filename unlinked was the same as the file whose descriptor you
498 hold.
499
500 unlink0($fh, $path)
501 or die "Error unlinking file $path safely";
502
503 Returns false on error but croaks() if there is a security anomaly.
504 The filehandle is not closed since on some occasions this is not
505 required.
506
507 On some platforms, for example Windows NT, it is not possible to
508 unlink an open file (the file must be closed first). On those
509 platforms, the actual unlinking is deferred until the program ends
510 and good status is returned. A check is still performed to make
511 sure that the filehandle and filename are pointing to the same
512 thing (but not at the time the end block is executed since the
513 deferred removal may not have access to the filehandle).
514
515 Additionally, on Windows NT not all the fields returned by stat()
516 can be compared. For example, the "dev" and "rdev" fields seem to
517 be different. Also, it seems that the size of the file returned by
518 stat() does not always agree, with "stat(FH)" being more accurate
519 than "stat(filename)", presumably because of caching issues even
520 when using autoflush (this is usually overcome by waiting a while
521 after writing to the tempfile before attempting to "unlink0" it).
522
523 Finally, on NFS file systems the link count of the file handle does
524 not always go to zero immediately after unlinking. Currently, this
525 command is expected to fail on NFS disks.
526
527 This function is disabled if the global variable $KEEP_ALL is true
528 and an unlink on open file is supported. If the unlink is to be
529 deferred to the END block, the file is still registered for
530 removal.
531
532 This function should not be called if you are using the object
533 oriented interface since the it will interfere with the object
534 destructor deleting the file.
535
536 cmpstat
537 Compare "stat" of filehandle with "stat" of provided filename.
538 This can be used to check that the filename and filehandle
539 initially point to the same file and that the number of links to
540 the file is 1 (all fields returned by stat() are compared).
541
542 cmpstat($fh, $path)
543 or die "Error comparing handle with file";
544
545 Returns false if the stat information differs or if the link count
546 is greater than 1. Calls croak if there is a security anomaly.
547
548 On certain platforms, for example Windows, not all the fields
549 returned by stat() can be compared. For example, the "dev" and
550 "rdev" fields seem to be different in Windows. Also, it seems that
551 the size of the file returned by stat() does not always agree, with
552 "stat(FH)" being more accurate than "stat(filename)", presumably
553 because of caching issues even when using autoflush (this is
554 usually overcome by waiting a while after writing to the tempfile
555 before attempting to "unlink0" it).
556
557 Not exported by default.
558
559 unlink1
560 Similar to "unlink0" except after file comparison using cmpstat,
561 the filehandle is closed prior to attempting to unlink the file.
562 This allows the file to be removed without using an END block, but
563 does mean that the post-unlink comparison of the filehandle state
564 provided by "unlink0" is not available.
565
566 unlink1($fh, $path)
567 or die "Error closing and unlinking file";
568
569 Usually called from the object destructor when using the OO
570 interface.
571
572 Not exported by default.
573
574 This function is disabled if the global variable $KEEP_ALL is true.
575
576 Can call croak() if there is a security anomaly during the stat()
577 comparison.
578
579 cleanup
580 Calling this function will cause any temp files or temp directories
581 that are registered for removal to be removed. This happens
582 automatically when the process exits but can be triggered manually
583 if the caller is sure that none of the temp files are required.
584 This method can be registered as an Apache callback.
585
586 Note that if a temp directory is your current directory, it cannot
587 be removed. "chdir()" out of the directory first before calling
588 "cleanup()". (For the cleanup at program exit when the CLEANUP flag
589 is set, this happens automatically.)
590
591 On OSes where temp files are automatically removed when the temp
592 file is closed, calling this function will have no effect other
593 than to remove temporary directories (which may include temporary
594 files).
595
596 File::Temp::cleanup();
597
598 Not exported by default.
599
601 These functions control the global state of the package.
602
603 safe_level
604 Controls the lengths to which the module will go to check the
605 safety of the temporary file or directory before proceeding.
606 Options are:
607
608 STANDARD
609 Do the basic security measures to ensure the directory
610 exists and is writable, that temporary files are opened
611 only if they do not already exist, and that possible race
612 conditions are avoided. Finally the unlink0 function is
613 used to remove files safely.
614
615 MEDIUM In addition to the STANDARD security, the output directory
616 is checked to make sure that it is owned either by root or
617 the user running the program. If the directory is writable
618 by group or by other, it is then checked to make sure that
619 the sticky bit is set.
620
621 Will not work on platforms that do not support the "-k"
622 test for sticky bit.
623
624 HIGH In addition to the MEDIUM security checks, also check for
625 the possibility of ``chown() giveaway'' using the POSIX
626 sysconf() function. If this is a possibility, each
627 directory in the path is checked in turn for safeness,
628 recursively walking back to the root directory.
629
630 For platforms that do not support the POSIX
631 "_PC_CHOWN_RESTRICTED" symbol (for example, Windows NT) it
632 is assumed that ``chown() giveaway'' is possible and the
633 recursive test is performed.
634
635 The level can be changed as follows:
636
637 File::Temp->safe_level( File::Temp::HIGH );
638
639 The level constants are not exported by the module.
640
641 Currently, you must be running at least perl v5.6.0 in order to run
642 with MEDIUM or HIGH security. This is simply because the safety
643 tests use functions from Fcntl that are not available in older
644 versions of perl. The problem is that the version number for Fcntl
645 is the same in perl 5.6.0 and in 5.005_03 even though they are
646 different versions.
647
648 On systems that do not support the HIGH or MEDIUM safety levels
649 (for example Win NT or OS/2) any attempt to change the level will
650 be ignored. The decision to ignore rather than raise an exception
651 allows portable programs to be written with high security in mind
652 for the systems that can support this without those programs
653 failing on systems where the extra tests are irrelevant.
654
655 If you really need to see whether the change has been accepted
656 simply examine the return value of "safe_level".
657
658 $newlevel = File::Temp->safe_level( File::Temp::HIGH );
659 die "Could not change to high security"
660 if $newlevel != File::Temp::HIGH;
661
662 TopSystemUID
663 This is the highest UID on the current system that refers to a root
664 UID. This is used to make sure that the temporary directory is
665 owned by a system UID ("root", "bin", "sys" etc) rather than simply
666 by root.
667
668 This is required since on many unix systems "/tmp" is not owned by
669 root.
670
671 Default is to assume that any UID less than or equal to 10 is a
672 root UID.
673
674 File::Temp->top_system_uid(10);
675 my $topid = File::Temp->top_system_uid;
676
677 This value can be adjusted to reduce security checking if required.
678 The value is only relevant when "safe_level" is set to MEDIUM or
679 higher.
680
681 $KEEP_ALL
682 Controls whether temporary files and directories should be retained
683 regardless of any instructions in the program to remove them
684 automatically. This is useful for debugging but should not be used
685 in production code.
686
687 $File::Temp::KEEP_ALL = 1;
688
689 Default is for files to be removed as requested by the caller.
690
691 In some cases, files will only be retained if this variable is true
692 when the file is created. This means that you can not create a
693 temporary file, set this variable and expect the temp file to still
694 be around when the program exits.
695
696 $DEBUG
697 Controls whether debugging messages should be enabled.
698
699 $File::Temp::DEBUG = 1;
700
701 Default is for debugging mode to be disabled.
702
704 For maximum security, endeavour always to avoid ever looking at,
705 touching, or even imputing the existence of the filename. You do not
706 know that that filename is connected to the same file as the handle you
707 have, and attempts to check this can only trigger more race conditions.
708 It's far more secure to use the filehandle alone and dispense with the
709 filename altogether.
710
711 If you need to pass the handle to something that expects a filename
712 then on a unix system you can use ""/dev/fd/" . fileno($fh)" for
713 arbitrary programs. Perl code that uses the 2-argument version of
714 "open" can be passed ""+<=&" . fileno($fh)". Otherwise you will need to
715 pass the filename. You will have to clear the close-on-exec bit on that
716 file descriptor before passing it to another process.
717
718 use Fcntl qw/F_SETFD F_GETFD/;
719 fcntl($tmpfh, F_SETFD, 0)
720 or die "Can't clear close-on-exec flag on temp fh: $!\n";
721
722 Temporary files and NFS
723 Some problems are associated with using temporary files that reside on
724 NFS file systems and it is recommended that a local filesystem is used
725 whenever possible. Some of the security tests will most probably fail
726 when the temp file is not local. Additionally, be aware that the
727 performance of I/O operations over NFS will not be as good as for a
728 local disk.
729
730 Forking
731 In some cases files created by File::Temp are removed from within an
732 END block. Since END blocks are triggered when a child process exits
733 (unless "POSIX::_exit()" is used by the child) File::Temp takes care to
734 only remove those temp files created by a particular process ID. This
735 means that a child will not attempt to remove temp files created by the
736 parent process.
737
738 If you are forking many processes in parallel that are all creating
739 temporary files, you may need to reset the random number seed using
740 srand(EXPR) in each child else all the children will attempt to walk
741 through the same set of random file names and may well cause themselves
742 to give up if they exceed the number of retry attempts.
743
744 Directory removal
745 Note that if you have chdir'ed into the temporary directory and it is
746 subsequently cleaned up (either in the END block or as part of object
747 destruction), then you will get a warning from File::Path::rmtree().
748
749 Taint mode
750 If you need to run code under taint mode, updating to the latest
751 File::Spec is highly recommended.
752
753 BINMODE
754 The file returned by File::Temp will have been opened in binary mode if
755 such a mode is available. If that is not correct, use the "binmode()"
756 function to change the mode of the filehandle.
757
758 Note that you can modify the encoding of a file opened by File::Temp
759 also by using "binmode()".
760
762 Originally began life in May 1999 as an XS interface to the system
763 mkstemp() function. In March 2000, the OpenBSD mkstemp() code was
764 translated to Perl for total control of the code's security checking,
765 to ensure the presence of the function regardless of operating system
766 and to help with portability. The module was shipped as a standard part
767 of perl from v5.6.1.
768
769 Thanks to Tom Christiansen for suggesting that this module should be
770 written and providing ideas for code improvements and security
771 enhancements.
772
774 "tmpnam" in POSIX, "tmpfile" in POSIX, File::Spec, File::Path
775
776 See IO::File and File::MkTemp, Apache::TempFile for different
777 implementations of temporary file handling.
778
779 See File::Tempdir for an alternative object-oriented wrapper for the
780 "tempdir" function.
781
782 # vim: ts=2 sts=2 sw=2 et:
783
785 Bugs / Feature Requests
786 Please report any bugs or feature requests through the issue tracker at
787 <https://rt.cpan.org/Public/Dist/Display.html?Name=File-Temp>. You
788 will be notified automatically of any progress on your issue.
789
790 Source Code
791 This is open source software. The code repository is available for
792 public review and contribution under the terms of the license.
793
794 <http://github.com/Perl-Toolchain-Gang/File-Temp>
795
796 git clone git://github.com/Perl-Toolchain-Gang/File-Temp.git
797
799 Tim Jenness <tjenness@cpan.org>
800
802 · Ben Tilly <btilly@gmail.com>
803
804 · David Golden <dagolden@cpan.org>
805
806 · Ed Avis <eda@linux01.wcl.local>
807
808 · James E. Keenan <jkeen@verizon.net>
809
810 · Kevin Ryde <user42@zip.com.au>
811
812 · Peter John Acklam <pjacklam@online.no>
813
815 This software is copyright (c) 2013 by Tim Jenness and the UK Particle
816 Physics and Astronomy Research Council.
817
818 This is free software; you can redistribute it and/or modify it under
819 the same terms as the Perl 5 programming language system itself.
820
821
822
823perl v5.16.3 2013-04-11 File::Temp(3)