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Diffstat (limited to 'contrib/perl5/lib/File/Temp.pm')
| -rw-r--r-- | contrib/perl5/lib/File/Temp.pm | 1863 |
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diff --git a/contrib/perl5/lib/File/Temp.pm b/contrib/perl5/lib/File/Temp.pm deleted file mode 100644 index b686682..0000000 --- a/contrib/perl5/lib/File/Temp.pm +++ /dev/null @@ -1,1863 +0,0 @@ -package File::Temp; - -=head1 NAME - -File::Temp - return name and handle of a temporary file safely - -=begin __INTERNALS - -=head1 PORTABILITY - -This module is designed to be portable across operating systems -and it currently supports Unix, VMS, DOS, OS/2 and Windows. When -porting to a new OS there are generally three main issues -that have to be solved: - -=over 4 - -=item * - -Can the OS unlink an open file? If it can not then the -C<_can_unlink_opened_file> method should be modified. - -=item * - -Are the return values from C<stat> reliable? By default all the -return values from C<stat> are compared when unlinking a temporary -file using the filename and the handle. Operating systems other than -unix do not always have valid entries in all fields. If C<unlink0> fails -then the C<stat> comparison should be modified accordingly. - -=item * - -Security. Systems that can not support a test for the sticky bit -on a directory can not use the MEDIUM and HIGH security tests. -The C<_can_do_level> method should be modified accordingly. - -=back - -=end __INTERNALS - -=head1 SYNOPSIS - - use File::Temp qw/ tempfile tempdir /; - - $dir = tempdir( CLEANUP => 1 ); - ($fh, $filename) = tempfile( DIR => $dir ); - - ($fh, $filename) = tempfile( $template, DIR => $dir); - ($fh, $filename) = tempfile( $template, SUFFIX => '.dat'); - - $fh = tempfile(); - -MkTemp family: - - use File::Temp qw/ :mktemp /; - - ($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, $file) = tmpnam(); - ($fh, $file) = tmpfile(); - - -Compatibility functions: - - $unopened_file = File::Temp::tempnam( $dir, $pfx ); - -=begin later - -Objects (NOT YET IMPLEMENTED): - - require File::Temp; - - $fh = new File::Temp($template); - $fname = $fh->filename; - -=end later - -=head1 DESCRIPTION - -C<File::Temp> can be used to create and open temporary files in a safe way. -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 L<"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 L<POSIX|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. - -=cut - -# 5.6.0 gives us S_IWOTH, S_IWGRP, our and auto-vivifying filehandls -# People would like a version on 5.005 so give them what they want :-) -use 5.005; -use strict; -use Carp; -use File::Spec 0.8; -use File::Path qw/ rmtree /; -use Fcntl 1.03; -use Errno; -require VMS::Stdio if $^O eq 'VMS'; - -# Need the Symbol package if we are running older perl -require Symbol if $] < 5.006; - - -# use 'our' on v5.6.0 -use vars qw($VERSION @EXPORT_OK %EXPORT_TAGS $DEBUG); - -$DEBUG = 0; - -# We are exporting functions - -use base qw/Exporter/; - -# Export list - to allow fine tuning of export table - -@EXPORT_OK = qw{ - tempfile - tempdir - tmpnam - tmpfile - mktemp - mkstemp - mkstemps - mkdtemp - unlink0 - }; - -# Groups of functions for export - -%EXPORT_TAGS = ( - 'POSIX' => [qw/ tmpnam tmpfile /], - 'mktemp' => [qw/ mktemp mkstemp mkstemps mkdtemp/], - ); - -# add contents of these tags to @EXPORT -Exporter::export_tags('POSIX','mktemp'); - -# Version number - -$VERSION = '0.12'; - -# This is a list of characters that can be used in random filenames - -my @CHARS = (qw/ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z - a b c d e f g h i j k l m n o p q r s t u v w x y z - 0 1 2 3 4 5 6 7 8 9 _ - /); - -# Maximum number of tries to make a temp file before failing - -use constant MAX_TRIES => 10; - -# Minimum number of X characters that should be in a template -use constant MINX => 4; - -# Default template when no template supplied - -use constant TEMPXXX => 'X' x 10; - -# Constants for the security level - -use constant STANDARD => 0; -use constant MEDIUM => 1; -use constant HIGH => 2; - -# OPENFLAGS. If we defined the flag to use with Sysopen here this gives -# us an optimisation when many temporary files are requested - -my $OPENFLAGS = O_CREAT | O_EXCL | O_RDWR; - -for my $oflag (qw/ FOLLOW BINARY LARGEFILE EXLOCK NOINHERIT /) { - my ($bit, $func) = (0, "Fcntl::O_" . $oflag); - no strict 'refs'; - $OPENFLAGS |= $bit if eval { - # Make sure that redefined die handlers do not cause problems - # eg CGI::Carp - local $SIG{__DIE__} = sub {}; - local $SIG{__WARN__} = sub {}; - $bit = &$func(); - 1; - }; -} - -# On some systems the O_TEMPORARY flag can be used to tell the OS -# to automatically remove the file when it is closed. This is fine -# in most cases but not if tempfile is called with UNLINK=>0 and -# the filename is requested -- in the case where the filename is to -# be passed to another routine. This happens on windows. We overcome -# this by using a second open flags variable - -my $OPENTEMPFLAGS = $OPENFLAGS; -for my $oflag (qw/ TEMPORARY /) { - my ($bit, $func) = (0, "Fcntl::O_" . $oflag); - no strict 'refs'; - $OPENTEMPFLAGS |= $bit if eval { - # Make sure that redefined die handlers do not cause problems - # eg CGI::Carp - local $SIG{__DIE__} = sub {}; - local $SIG{__WARN__} = sub {}; - $bit = &$func(); - 1; - }; -} - -# INTERNAL ROUTINES - not to be used outside of package - -# Generic routine for getting a temporary filename -# modelled on OpenBSD _gettemp() in mktemp.c - -# The template must contain X's that are to be replaced -# with the random values - -# Arguments: - -# TEMPLATE - string containing the XXXXX's that is converted -# to a random filename and opened if required - -# Optionally, a hash can also be supplied containing specific options -# "open" => if true open the temp file, else just return the name -# default is 0 -# "mkdir"=> if true, we are creating a temp directory rather than tempfile -# default is 0 -# "suffixlen" => number of characters at end of PATH to be ignored. -# default is 0. -# "unlink_on_close" => indicates that, if possible, the OS should remove -# the file as soon as it is closed. Usually indicates -# use of the O_TEMPORARY flag to sysopen. -# Usually irrelevant on unix - -# Optionally a reference to a scalar can be passed into the function -# On error this will be used to store the reason for the error -# "ErrStr" => \$errstr - -# "open" and "mkdir" can not both be true -# "unlink_on_close" is not used when "mkdir" is true. - -# The default options are equivalent to mktemp(). - -# Returns: -# filehandle - open file handle (if called with doopen=1, else undef) -# temp name - name of the temp file or directory - -# For example: -# ($fh, $name) = _gettemp($template, "open" => 1); - -# for the current version, failures are associated with -# stored in an error string and returned to give the reason whilst debugging -# This routine is not called by any external function -sub _gettemp { - - croak 'Usage: ($fh, $name) = _gettemp($template, OPTIONS);' - unless scalar(@_) >= 1; - - # the internal error string - expect it to be overridden - # Need this in case the caller decides not to supply us a value - # need an anonymous scalar - my $tempErrStr; - - # Default options - my %options = ( - "open" => 0, - "mkdir" => 0, - "suffixlen" => 0, - "unlink_on_close" => 0, - "ErrStr" => \$tempErrStr, - ); - - # Read the template - my $template = shift; - if (ref($template)) { - # Use a warning here since we have not yet merged ErrStr - carp "File::Temp::_gettemp: template must not be a reference"; - return (); - } - - # Check that the number of entries on stack are even - if (scalar(@_) % 2 != 0) { - # Use a warning here since we have not yet merged ErrStr - carp "File::Temp::_gettemp: Must have even number of options"; - return (); - } - - # Read the options and merge with defaults - %options = (%options, @_) if @_; - - # Make sure the error string is set to undef - ${$options{ErrStr}} = undef; - - # Can not open the file and make a directory in a single call - if ($options{"open"} && $options{"mkdir"}) { - ${$options{ErrStr}} = "doopen and domkdir can not both be true\n"; - return (); - } - - # Find the start of the end of the Xs (position of last X) - # Substr starts from 0 - my $start = length($template) - 1 - $options{"suffixlen"}; - - # Check that we have at least MINX x X (eg 'XXXX") at the end of the string - # (taking suffixlen into account). Any fewer is insecure. - - # Do it using substr - no reason to use a pattern match since - # we know where we are looking and what we are looking for - - if (substr($template, $start - MINX + 1, MINX) ne 'X' x MINX) { - ${$options{ErrStr}} = "The template must contain at least ". - MINX . " 'X' characters\n"; - return (); - } - - # Replace all the X at the end of the substring with a - # random character or just all the XX at the end of a full string. - # Do it as an if, since the suffix adjusts which section to replace - # and suffixlen=0 returns nothing if used in the substr directly - # and generate a full path from the template - - my $path = _replace_XX($template, $options{"suffixlen"}); - - - # Split the path into constituent parts - eventually we need to check - # whether the directory exists - # We need to know whether we are making a temp directory - # or a tempfile - - my ($volume, $directories, $file); - my $parent; # parent directory - if ($options{"mkdir"}) { - # There is no filename at the end - ($volume, $directories, $file) = File::Spec->splitpath( $path, 1); - - # The parent is then $directories without the last directory - # Split the directory and put it back together again - my @dirs = File::Spec->splitdir($directories); - - # If @dirs only has one entry that means we are in the current - # directory - if ($#dirs == 0) { - $parent = File::Spec->curdir; - } else { - - if ($^O eq 'VMS') { # need volume to avoid relative dir spec - $parent = File::Spec->catdir($volume, @dirs[0..$#dirs-1]); - $parent = 'sys$disk:[]' if $parent eq ''; - } else { - - # Put it back together without the last one - $parent = File::Spec->catdir(@dirs[0..$#dirs-1]); - - # ...and attach the volume (no filename) - $parent = File::Spec->catpath($volume, $parent, ''); - } - - } - - } else { - - # Get rid of the last filename (use File::Basename for this?) - ($volume, $directories, $file) = File::Spec->splitpath( $path ); - - # Join up without the file part - $parent = File::Spec->catpath($volume,$directories,''); - - # If $parent is empty replace with curdir - $parent = File::Spec->curdir - unless $directories ne ''; - - } - - # Check that the parent directories exist - # Do this even for the case where we are simply returning a name - # not a file -- no point returning a name that includes a directory - # that does not exist or is not writable - - unless (-d $parent) { - ${$options{ErrStr}} = "Parent directory ($parent) is not a directory"; - return (); - } - unless (-w _) { - ${$options{ErrStr}} = "Parent directory ($parent) is not writable\n"; - return (); - } - - - # Check the stickiness of the directory and chown giveaway if required - # If the directory is world writable the sticky bit - # must be set - - if (File::Temp->safe_level == MEDIUM) { - my $safeerr; - unless (_is_safe($parent,\$safeerr)) { - ${$options{ErrStr}} = "Parent directory ($parent) is not safe ($safeerr)"; - return (); - } - } elsif (File::Temp->safe_level == HIGH) { - my $safeerr; - unless (_is_verysafe($parent, \$safeerr)) { - ${$options{ErrStr}} = "Parent directory ($parent) is not safe ($safeerr)"; - return (); - } - } - - - # Now try MAX_TRIES time to open the file - for (my $i = 0; $i < MAX_TRIES; $i++) { - - # Try to open the file if requested - if ($options{"open"}) { - my $fh; - - # If we are running before perl5.6.0 we can not auto-vivify - if ($] < 5.006) { - $fh = &Symbol::gensym; - } - - # Try to make sure this will be marked close-on-exec - # XXX: Win32 doesn't respect this, nor the proper fcntl, - # but may have O_NOINHERIT. This may or may not be in Fcntl. - local $^F = 2; - - # Store callers umask - my $umask = umask(); - - # Set a known umask - umask(066); - - # Attempt to open the file - my $open_success = undef; - if ( $^O eq 'VMS' and $options{"unlink_on_close"} ) { - # make it auto delete on close by setting FAB$V_DLT bit - $fh = VMS::Stdio::vmssysopen($path, $OPENFLAGS, 0600, 'fop=dlt'); - $open_success = $fh; - } else { - my $flags = ( $options{"unlink_on_close"} ? - $OPENTEMPFLAGS : - $OPENFLAGS ); - $open_success = sysopen($fh, $path, $flags, 0600); - } - if ( $open_success ) { - - # Reset umask - umask($umask); - - # Opened successfully - return file handle and name - return ($fh, $path); - - } else { - # Reset umask - umask($umask); - - # Error opening file - abort with error - # if the reason was anything but EEXIST - unless ($!{EEXIST}) { - ${$options{ErrStr}} = "Could not create temp file $path: $!"; - return (); - } - - # Loop round for another try - - } - } elsif ($options{"mkdir"}) { - - # Store callers umask - my $umask = umask(); - - # Set a known umask - umask(066); - - # Open the temp directory - if (mkdir( $path, 0700)) { - # created okay - # Reset umask - umask($umask); - - return undef, $path; - } else { - - # Reset umask - umask($umask); - - # Abort with error if the reason for failure was anything - # except EEXIST - unless ($!{EEXIST}) { - ${$options{ErrStr}} = "Could not create directory $path: $!"; - return (); - } - - # Loop round for another try - - } - - } else { - - # Return true if the file can not be found - # Directory has been checked previously - - return (undef, $path) unless -e $path; - - # Try again until MAX_TRIES - - } - - # Did not successfully open the tempfile/dir - # so try again with a different set of random letters - # No point in trying to increment unless we have only - # 1 X say and the randomness could come up with the same - # file MAX_TRIES in a row. - - # Store current attempt - in principal this implies that the - # 3rd time around the open attempt that the first temp file - # name could be generated again. Probably should store each - # attempt and make sure that none are repeated - - my $original = $path; - my $counter = 0; # Stop infinite loop - my $MAX_GUESS = 50; - - do { - - # Generate new name from original template - $path = _replace_XX($template, $options{"suffixlen"}); - - $counter++; - - } until ($path ne $original || $counter > $MAX_GUESS); - - # Check for out of control looping - if ($counter > $MAX_GUESS) { - ${$options{ErrStr}} = "Tried to get a new temp name different to the previous value $MAX_GUESS times.\nSomething wrong with template?? ($template)"; - return (); - } - - } - - # If we get here, we have run out of tries - ${ $options{ErrStr} } = "Have exceeded the maximum number of attempts (" - . MAX_TRIES . ") to open temp file/dir"; - - return (); - -} - -# Internal routine to return a random character from the -# character list. Does not do an srand() since rand() -# will do one automatically - -# No arguments. Return value is the random character - -# No longer called since _replace_XX runs a few percent faster if -# I inline the code. This is important if we are creating thousands of -# temporary files. - -sub _randchar { - - $CHARS[ int( rand( $#CHARS ) ) ]; - -} - -# Internal routine to replace the XXXX... with random characters -# This has to be done by _gettemp() every time it fails to -# open a temp file/dir - -# Arguments: $template (the template with XXX), -# $ignore (number of characters at end to ignore) - -# Returns: modified template - -sub _replace_XX { - - croak 'Usage: _replace_XX($template, $ignore)' - unless scalar(@_) == 2; - - my ($path, $ignore) = @_; - - # Do it as an if, since the suffix adjusts which section to replace - # and suffixlen=0 returns nothing if used in the substr directly - # Alternatively, could simply set $ignore to length($path)-1 - # Don't want to always use substr when not required though. - - if ($ignore) { - substr($path, 0, - $ignore) =~ s/X(?=X*\z)/$CHARS[ int( rand( $#CHARS ) ) ]/ge; - } else { - $path =~ s/X(?=X*\z)/$CHARS[ int( rand( $#CHARS ) ) ]/ge; - } - - return $path; -} - -# internal routine to check to see if the directory is safe -# First checks to see if the directory is not owned by the -# current user or root. Then checks to see if anyone else -# can write to the directory and if so, checks to see if -# it has the sticky bit set - -# Will not work on systems that do not support sticky bit - -#Args: directory path to check -# Optionally: reference to scalar to contain error message -# Returns true if the path is safe and false otherwise. -# Returns undef if can not even run stat() on the path - -# This routine based on version written by Tom Christiansen - -# Presumably, by the time we actually attempt to create the -# file or directory in this directory, it may not be safe -# anymore... Have to run _is_safe directly after the open. - -sub _is_safe { - - my $path = shift; - my $err_ref = shift; - - # Stat path - my @info = stat($path); - unless (scalar(@info)) { - $$err_ref = "stat(path) returned no values"; - return 0; - }; - return 1 if $^O eq 'VMS'; # owner delete control at file level - - # Check to see whether owner is neither superuser (or a system uid) nor me - # Use the real uid from the $< variable - # UID is in [4] - if ($info[4] > File::Temp->top_system_uid() && $info[4] != $<) { - - Carp::cluck(sprintf "uid=$info[4] topuid=%s \$<=$< path='$path'", - File::Temp->top_system_uid()); - - $$err_ref = "Directory owned neither by root nor the current user" - if ref($err_ref); - return 0; - } - - # check whether group or other can write file - # use 066 to detect either reading or writing - # use 022 to check writability - # Do it with S_IWOTH and S_IWGRP for portability (maybe) - # mode is in info[2] - if (($info[2] & &Fcntl::S_IWGRP) || # Is group writable? - ($info[2] & &Fcntl::S_IWOTH) ) { # Is world writable? - # Must be a directory - unless (-d _) { - $$err_ref = "Path ($path) is not a directory" - if ref($err_ref); - return 0; - } - # Must have sticky bit set - unless (-k _) { - $$err_ref = "Sticky bit not set on $path when dir is group|world writable" - if ref($err_ref); - return 0; - } - } - - return 1; -} - -# Internal routine to check whether a directory is safe -# for temp files. Safer than _is_safe since it checks for -# the possibility of chown giveaway and if that is a possibility -# checks each directory in the path to see if it is safe (with _is_safe) - -# If _PC_CHOWN_RESTRICTED is not set, does the full test of each -# directory anyway. - -# Takes optional second arg as scalar ref to error reason - -sub _is_verysafe { - - # Need POSIX - but only want to bother if really necessary due to overhead - require POSIX; - - my $path = shift; - print "_is_verysafe testing $path\n" if $DEBUG; - return 1 if $^O eq 'VMS'; # owner delete control at file level - - my $err_ref = shift; - - # Should Get the value of _PC_CHOWN_RESTRICTED if it is defined - # and If it is not there do the extensive test - my $chown_restricted; - $chown_restricted = &POSIX::_PC_CHOWN_RESTRICTED() - if eval { &POSIX::_PC_CHOWN_RESTRICTED(); 1}; - - # If chown_resticted is set to some value we should test it - if (defined $chown_restricted) { - - # Return if the current directory is safe - return _is_safe($path,$err_ref) if POSIX::sysconf( $chown_restricted ); - - } - - # To reach this point either, the _PC_CHOWN_RESTRICTED symbol - # was not avialable or the symbol was there but chown giveaway - # is allowed. Either way, we now have to test the entire tree for - # safety. - - # Convert path to an absolute directory if required - unless (File::Spec->file_name_is_absolute($path)) { - $path = File::Spec->rel2abs($path); - } - - # Split directory into components - assume no file - my ($volume, $directories, undef) = File::Spec->splitpath( $path, 1); - - # Slightly less efficient than having a a function in File::Spec - # to chop off the end of a directory or even a function that - # can handle ../ in a directory tree - # Sometimes splitdir() returns a blank at the end - # so we will probably check the bottom directory twice in some cases - my @dirs = File::Spec->splitdir($directories); - - # Concatenate one less directory each time around - foreach my $pos (0.. $#dirs) { - # Get a directory name - my $dir = File::Spec->catpath($volume, - File::Spec->catdir(@dirs[0.. $#dirs - $pos]), - '' - ); - - print "TESTING DIR $dir\n" if $DEBUG; - - # Check the directory - return 0 unless _is_safe($dir,$err_ref); - - } - - return 1; -} - - - -# internal routine to determine whether unlink works on this -# platform for files that are currently open. -# Returns true if we can, false otherwise. - -# Currently WinNT, OS/2 and VMS can not unlink an opened file -# On VMS this is because the O_EXCL flag is used to open the -# temporary file. Currently I do not know enough about the issues -# on VMS to decide whether O_EXCL is a requirement. - -sub _can_unlink_opened_file { - - if ($^O eq 'MSWin32' || $^O eq 'os2' || $^O eq 'VMS' || $^O eq 'dos') { - return 0; - } else { - return 1; - } - -} - -# internal routine to decide which security levels are allowed -# see safe_level() for more information on this - -# Controls whether the supplied security level is allowed - -# $cando = _can_do_level( $level ) - -sub _can_do_level { - - # Get security level - my $level = shift; - - # Always have to be able to do STANDARD - return 1 if $level == STANDARD; - - # Currently, the systems that can do HIGH or MEDIUM are identical - if ( $^O eq 'MSWin32' || $^O eq 'os2' || $^O eq 'cygwin' || $^O eq 'dos') { - return 0; - } else { - return 1; - } - -} - -# This routine sets up a deferred unlinking of a specified -# filename and filehandle. It is used in the following cases: -# - Called by unlink0 if an opened file can not be unlinked -# - Called by tempfile() if files are to be removed on shutdown -# - Called by tempdir() if directories are to be removed on shutdown - -# Arguments: -# _deferred_unlink( $fh, $fname, $isdir ); -# -# - filehandle (so that it can be expclicitly closed if open -# - filename (the thing we want to remove) -# - isdir (flag to indicate that we are being given a directory) -# [and hence no filehandle] - -# Status is not referred to since all the magic is done with an END block - -{ - # Will set up two lexical variables to contain all the files to be - # removed. One array for files, another for directories - # They will only exist in this block - # This means we only have to set up a single END block to remove all files - # @files_to_unlink contains an array ref with the filehandle and filename - my (@files_to_unlink, @dirs_to_unlink); - - # Set up an end block to use these arrays - END { - # Files - foreach my $file (@files_to_unlink) { - # close the filehandle without checking its state - # in order to make real sure that this is closed - # if its already closed then I dont care about the answer - # probably a better way to do this - close($file->[0]); # file handle is [0] - - if (-f $file->[1]) { # file name is [1] - unlink $file->[1] or warn "Error removing ".$file->[1]; - } - } - # Dirs - foreach my $dir (@dirs_to_unlink) { - if (-d $dir) { - rmtree($dir, $DEBUG, 1); - } - } - - } - - # This is the sub called to register a file for deferred unlinking - # This could simply store the input parameters and defer everything - # until the END block. For now we do a bit of checking at this - # point in order to make sure that (1) we have a file/dir to delete - # and (2) we have been called with the correct arguments. - sub _deferred_unlink { - - croak 'Usage: _deferred_unlink($fh, $fname, $isdir)' - unless scalar(@_) == 3; - - my ($fh, $fname, $isdir) = @_; - - warn "Setting up deferred removal of $fname\n" - if $DEBUG; - - # If we have a directory, check that it is a directory - if ($isdir) { - - if (-d $fname) { - - # Directory exists so store it - # first on VMS turn []foo into [.foo] for rmtree - $fname = VMS::Filespec::vmspath($fname) if $^O eq 'VMS'; - push (@dirs_to_unlink, $fname); - - } else { - carp "Request to remove directory $fname could not be completed since it does not exist!\n" if $^W; - } - - } else { - - if (-f $fname) { - - # file exists so store handle and name for later removal - push(@files_to_unlink, [$fh, $fname]); - - } else { - carp "Request to remove file $fname could not be completed since it is not there!\n" if $^W; - } - - } - - } - - -} - -=head1 FUNCTIONS - -This section describes the recommended interface for generating -temporary files and directories. - -=over 4 - -=item B<tempfile> - -This is the basic function to generate temporary files. -The behaviour of the file can be changed using various options: - - ($fh, $filename) = tempfile(); - -Create a temporary file in the directory specified for temporary -files, as specified by the tmpdir() function in L<File::Spec>. - - ($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 -in 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, UNLINK => 1); - -Return the filename and filehandle as before except that the file is -automatically removed when the program exits. 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 on exit or when it is closed. - -If the template is not specified, a template is always -automatically generated. This temporary file is placed in tmpdir() -(L<File::Spec>) unless a directory is specified explicitly with the -DIR option. - - $fh = tempfile( $template, DIR => $dir ); - -If called in scalar context, only the filehandle is returned -and the file will automatically be deleted when closed (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 C<O_TEMPORARY> flag)) -the file is marked for deletion when the program ends (equivalent -to setting UNLINK to 1). The C<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. - -Options can be combined as required. - -=cut - -sub tempfile { - - # Can not check for argument count since we can have any - # number of args - - # Default options - my %options = ( - "DIR" => undef, # Directory prefix - "SUFFIX" => '', # Template suffix - "UNLINK" => 0, # Do not unlink file on exit - "OPEN" => 1, # Open file - ); - - # Check to see whether we have an odd or even number of arguments - my $template = (scalar(@_) % 2 == 1 ? shift(@_) : undef); - - # Read the options and merge with defaults - %options = (%options, @_) if @_; - - # First decision is whether or not to open the file - if (! $options{"OPEN"}) { - - warn "tempfile(): temporary filename requested but not opened.\nPossibly unsafe, consider using tempfile() with OPEN set to true\n" - if $^W; - - } - - if ($options{"DIR"} and $^O eq 'VMS') { - - # on VMS turn []foo into [.foo] for concatenation - $options{"DIR"} = VMS::Filespec::vmspath($options{"DIR"}); - } - - # Construct the template - - # Have a choice of trying to work around the mkstemp/mktemp/tmpnam etc - # functions or simply constructing a template and using _gettemp() - # explicitly. Go for the latter - - # First generate a template if not defined and prefix the directory - # If no template must prefix the temp directory - if (defined $template) { - if ($options{"DIR"}) { - - $template = File::Spec->catfile($options{"DIR"}, $template); - - } - - } else { - - if ($options{"DIR"}) { - - $template = File::Spec->catfile($options{"DIR"}, TEMPXXX); - - } else { - - $template = File::Spec->catfile(File::Spec->tmpdir, TEMPXXX); - - } - - } - - # Now add a suffix - $template .= $options{"SUFFIX"}; - - # Determine whether we should tell _gettemp to unlink the file - # On unix this is irrelevant and can be worked out after the file is - # opened (simply by unlinking the open filehandle). On Windows or VMS - # we have to indicate temporary-ness when we open the file. In general - # we only want a true temporary file if we are returning just the - # filehandle - if the user wants the filename they probably do not - # want the file to disappear as soon as they close it. - # For this reason, tie unlink_on_close to the return context regardless - # of OS. - my $unlink_on_close = ( wantarray ? 0 : 1); - - # Create the file - my ($fh, $path, $errstr); - croak "Error in tempfile() using $template: $errstr" - unless (($fh, $path) = _gettemp($template, - "open" => $options{'OPEN'}, - "mkdir"=> 0 , - "unlink_on_close" => $unlink_on_close, - "suffixlen" => length($options{'SUFFIX'}), - "ErrStr" => \$errstr, - ) ); - - # Set up an exit handler that can do whatever is right for the - # system. This removes files at exit when requested explicitly or when - # system is asked to unlink_on_close but is unable to do so because - # of OS limitations. - # The latter should be achieved by using a tied filehandle. - # Do not check return status since this is all done with END blocks. - _deferred_unlink($fh, $path, 0) if $options{"UNLINK"}; - - # Return - if (wantarray()) { - - if ($options{'OPEN'}) { - return ($fh, $path); - } else { - return (undef, $path); - } - - } else { - - # Unlink the file. It is up to unlink0 to decide what to do with - # this (whether to unlink now or to defer until later) - unlink0($fh, $path) or croak "Error unlinking file $path using unlink0"; - - # Return just the filehandle. - return $fh; - } - - -} - -=item B<tempdir> - -This is the recommended interface for creation of temporary directories. -The behaviour of the function depends on the arguments: - - $tempdir = tempdir(); - -Create a directory in tmpdir() (see L<File::Spec|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, creat 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 C<TMPDIR> option is ignored if C<DIR> is set -explicitly. Additionally, C<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 L<File::Path|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. - -=cut - -# ' - -sub tempdir { - - # Can not check for argument count since we can have any - # number of args - - # Default options - my %options = ( - "CLEANUP" => 0, # Remove directory on exit - "DIR" => '', # Root directory - "TMPDIR" => 0, # Use tempdir with template - ); - - # Check to see whether we have an odd or even number of arguments - my $template = (scalar(@_) % 2 == 1 ? shift(@_) : undef ); - - # Read the options and merge with defaults - %options = (%options, @_) if @_; - - # Modify or generate the template - - # Deal with the DIR and TMPDIR options - if (defined $template) { - - # Need to strip directory path if using DIR or TMPDIR - if ($options{'TMPDIR'} || $options{'DIR'}) { - - # Strip parent directory from the filename - # - # There is no filename at the end - $template = VMS::Filespec::vmspath($template) if $^O eq 'VMS'; - my ($volume, $directories, undef) = File::Spec->splitpath( $template, 1); - - # Last directory is then our template - $template = (File::Spec->splitdir($directories))[-1]; - - # Prepend the supplied directory or temp dir - if ($options{"DIR"}) { - - $template = File::Spec->catdir($options{"DIR"}, $template); - - } elsif ($options{TMPDIR}) { - - # Prepend tmpdir - $template = File::Spec->catdir(File::Spec->tmpdir, $template); - - } - - } - - } else { - - if ($options{"DIR"}) { - - $template = File::Spec->catdir($options{"DIR"}, TEMPXXX); - - } else { - - $template = File::Spec->catdir(File::Spec->tmpdir, TEMPXXX); - - } - - } - - # Create the directory - my $tempdir; - my $suffixlen = 0; - if ($^O eq 'VMS') { # dir names can end in delimiters - $template =~ m/([\.\]:>]+)$/; - $suffixlen = length($1); - } - - my $errstr; - croak "Error in tempdir() using $template: $errstr" - unless ((undef, $tempdir) = _gettemp($template, - "open" => 0, - "mkdir"=> 1 , - "suffixlen" => $suffixlen, - "ErrStr" => \$errstr, - ) ); - - # Install exit handler; must be dynamic to get lexical - if ( $options{'CLEANUP'} && -d $tempdir) { - _deferred_unlink(undef, $tempdir, 1); - } - - # Return the dir name - return $tempdir; - -} - -=back - -=head1 MKTEMP FUNCTIONS - -The following functions are Perl implementations of the -mktemp() family of temp file generation system calls. - -=over 4 - -=item B<mkstemp> - -Given a template, returns a filehandle to the temporary file and the name -of the file. - - ($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 F</tmp/temp.XXXX>. The trailing X's are replaced -with unique alphanumeric combinations. - -=cut - - - -sub mkstemp { - - croak "Usage: mkstemp(template)" - if scalar(@_) != 1; - - my $template = shift; - - my ($fh, $path, $errstr); - croak "Error in mkstemp using $template: $errstr" - unless (($fh, $path) = _gettemp($template, - "open" => 1, - "mkdir"=> 0 , - "suffixlen" => 0, - "ErrStr" => \$errstr, - ) ); - - if (wantarray()) { - return ($fh, $path); - } else { - return $fh; - } - -} - - -=item B<mkstemps> - -Similar to mkstemp(), except that an extra argument can be supplied -with a suffix to be appended to the template. - - ($fh, $name) = mkstemps( $template, $suffix ); - -For example a template of C<testXXXXXX> and suffix of C<.dat> -would generate a file similar to F<testhGji_w.dat>. - -Returns just the filehandle alone when called in scalar context. - -=cut - -sub mkstemps { - - croak "Usage: mkstemps(template, suffix)" - if scalar(@_) != 2; - - - my $template = shift; - my $suffix = shift; - - $template .= $suffix; - - my ($fh, $path, $errstr); - croak "Error in mkstemps using $template: $errstr" - unless (($fh, $path) = _gettemp($template, - "open" => 1, - "mkdir"=> 0 , - "suffixlen" => length($suffix), - "ErrStr" => \$errstr, - ) ); - - if (wantarray()) { - return ($fh, $path); - } else { - return $fh; - } - -} - -=item B<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. -Returns undef on failure. - -Directory must be removed by the caller. - -=cut - -#' # for emacs - -sub mkdtemp { - - croak "Usage: mkdtemp(template)" - if scalar(@_) != 1; - - my $template = shift; - my $suffixlen = 0; - if ($^O eq 'VMS') { # dir names can end in delimiters - $template =~ m/([\.\]:>]+)$/; - $suffixlen = length($1); - } - my ($junk, $tmpdir, $errstr); - croak "Error creating temp directory from template $template\: $errstr" - unless (($junk, $tmpdir) = _gettemp($template, - "open" => 0, - "mkdir"=> 1 , - "suffixlen" => $suffixlen, - "ErrStr" => \$errstr, - ) ); - - return $tmpdir; - -} - -=item B<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(). - -=cut - -sub mktemp { - - croak "Usage: mktemp(template)" - if scalar(@_) != 1; - - my $template = shift; - - my ($tmpname, $junk, $errstr); - croak "Error getting name to temp file from template $template: $errstr" - unless (($junk, $tmpname) = _gettemp($template, - "open" => 0, - "mkdir"=> 0 , - "suffixlen" => 0, - "ErrStr" => \$errstr, - ) ); - - return $tmpname; -} - -=back - -=head1 POSIX FUNCTIONS - -This section describes the re-implementation of the tmpnam() -and tmpfile() functions described in L<POSIX> -using the mkstemp() from this module. - -Unlike the L<POSIX|POSIX> implementations, the directory used -for the temporary file is not specified in a system include -file (C<P_tmpdir>) but simply depends on the choice of tmpdir() -returned by L<File::Spec|File::Spec>. On some implementations this -location can be set using the C<TMPDIR> environment variable, which -may not be secure. -If this is a problem, simply use mkstemp() and specify a template. - -=over 4 - -=item B<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 L<File::Spec/tmpdir> for information on the choice of temporary -directory for a particular operating system. - -=cut - -sub tmpnam { - - # Retrieve the temporary directory name - my $tmpdir = File::Spec->tmpdir; - - croak "Error temporary directory is not writable" - if $tmpdir eq ''; - - # Use a ten character template and append to tmpdir - my $template = File::Spec->catfile($tmpdir, TEMPXXX); - - if (wantarray() ) { - return mkstemp($template); - } else { - return mktemp($template); - } - -} - -=item B<tmpfile> - -In scalar context, returns the filehandle of a temporary file. - - $fh = tmpfile(); - -The file is removed when the filehandle is closed or when the program -exits. No access to the filename is provided. - -If the temporary file can not be created undef is returned. -Currently this command will probably not work when the temporary -directory is on an NFS file system. - -=cut - -sub tmpfile { - - # Simply call tmpnam() in a list context - my ($fh, $file) = tmpnam(); - - # Make sure file is removed when filehandle is closed - # This will fail on NFS - unlink0($fh, $file) - or return undef; - - return $fh; - -} - -=back - -=head1 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. - -=over 4 - -=item B<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 C<sysopen> -with C<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. - -=cut - -sub tempnam { - - croak 'Usage tempnam($dir, $prefix)' unless scalar(@_) == 2; - - my ($dir, $prefix) = @_; - - # Add a string to the prefix - $prefix .= 'XXXXXXXX'; - - # Concatenate the directory to the file - my $template = File::Spec->catfile($dir, $prefix); - - return mktemp($template); - -} - -=back - -=head1 UTILITY FUNCTIONS - -Useful functions for dealing with the filehandle and filename. - -=over 4 - -=item B<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 $path safely"; - -Returns false on error. The filehandle is not closed since on some -occasions this is not required. - -On some platforms, for example Windows NT, it is not possible to -unlink an open file (the file must be closed first). On those -platforms, the actual unlinking is deferred until the program ends and -good status is returned. A check is still performed to make sure that -the filehandle and filename are pointing to the same thing (but not at -the time the end block is executed since the deferred removal may not -have access to the filehandle). - -Additionally, on Windows NT not all the fields returned by stat() can -be compared. For example, the C<dev> and C<rdev> fields seem to be -different. Also, it seems that the size of the file returned by stat() -does not always agree, with C<stat(FH)> being more accurate than -C<stat(filename)>, presumably because of caching issues even when -using autoflush (this is usually overcome by waiting a while after -writing to the tempfile before attempting to C<unlink0> it). - -Finally, on NFS file systems the link count of the file handle does -not always go to zero immediately after unlinking. Currently, this -command is expected to fail on NFS disks. - -=cut - -sub unlink0 { - - croak 'Usage: unlink0(filehandle, filename)' - unless scalar(@_) == 2; - - # Read args - my ($fh, $path) = @_; - - warn "Unlinking $path using unlink0\n" - if $DEBUG; - - # Stat the filehandle - my @fh = stat $fh; - - if ($fh[3] > 1 && $^W) { - carp "unlink0: fstat found too many links; SB=@fh" if $^W; - } - - # Stat the path - my @path = stat $path; - - unless (@path) { - carp "unlink0: $path is gone already" if $^W; - return; - } - - # this is no longer a file, but may be a directory, or worse - unless (-f _) { - confess "panic: $path is no longer a file: SB=@fh"; - } - - # Do comparison of each member of the array - # On WinNT dev and rdev seem to be different - # depending on whether it is a file or a handle. - # Cannot simply compare all members of the stat return - # Select the ones we can use - my @okstat = (0..$#fh); # Use all by default - if ($^O eq 'MSWin32') { - @okstat = (1,2,3,4,5,7,8,9,10); - } elsif ($^O eq 'os2') { - @okstat = (0, 2..$#fh); - } elsif ($^O eq 'VMS') { # device and file ID are sufficient - @okstat = (0, 1); - } elsif ($^O eq 'dos') { - @okstat = (0,2..7,11..$#fh); - } - - # Now compare each entry explicitly by number - for (@okstat) { - print "Comparing: $_ : $fh[$_] and $path[$_]\n" if $DEBUG; - # Use eq rather than == since rdev, blksize, and blocks (6, 11, - # and 12) will be '' on platforms that do not support them. This - # is fine since we are only comparing integers. - unless ($fh[$_] eq $path[$_]) { - warn "Did not match $_ element of stat\n" if $DEBUG; - return 0; - } - } - - # attempt remove the file (does not work on some platforms) - if (_can_unlink_opened_file()) { - # XXX: do *not* call this on a directory; possible race - # resulting in recursive removal - croak "unlink0: $path has become a directory!" if -d $path; - unlink($path) or return 0; - - # Stat the filehandle - @fh = stat $fh; - - print "Link count = $fh[3] \n" if $DEBUG; - - # Make sure that the link count is zero - # - Cygwin provides deferred unlinking, however, - # on Win9x the link count remains 1 - # On NFS the link count may still be 1 but we cant know that - # we are on NFS - return ( $fh[3] == 0 or $^O eq 'cygwin' ? 1 : 0); - - } else { - _deferred_unlink($fh, $path, 0); - return 1; - } - -} - -=back - -=head1 PACKAGE VARIABLES - -These functions control the global state of the package. - -=over 4 - -=item B<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: - -=over 8 - -=item STANDARD - -Do the basic security measures to ensure the directory exists and -is writable, that the umask() is fixed before opening of the file, -that temporary files are opened only if they do not already exist, and -that possible race conditions are avoided. Finally the L<unlink0|"unlink0"> -function is used to remove files safely. - -=item 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 C<-k> test -for sticky bit. - -=item HIGH - -In addition to the MEDIUM security checks, also check for the -possibility of ``chown() giveaway'' using the L<POSIX|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 L<POSIX|POSIX> -C<_PC_CHOWN_RESTRICTED> symbol (for example, Windows NT) it is -assumed that ``chown() giveaway'' is possible and the recursive test -is performed. - -=back - -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 L<Fcntl|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 C<safe_level>. - - $newlevel = File::Temp->safe_level( File::Temp::HIGH ); - die "Could not change to high security" - if $newlevel != File::Temp::HIGH; - -=cut - -{ - # protect from using the variable itself - my $LEVEL = STANDARD; - sub safe_level { - my $self = shift; - if (@_) { - my $level = shift; - if (($level != STANDARD) && ($level != MEDIUM) && ($level != HIGH)) { - carp "safe_level: Specified level ($level) not STANDARD, MEDIUM or HIGH - ignoring\n" if $^W; - } else { - # Dont allow this on perl 5.005 or earlier - if ($] < 5.006 && $level != STANDARD) { - # Cant do MEDIUM or HIGH checks - croak "Currently requires perl 5.006 or newer to do the safe checks"; - } - # Check that we are allowed to change level - # Silently ignore if we can not. - $LEVEL = $level if _can_do_level($level); - } - } - return $LEVEL; - } -} - -=item 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 (C<root>, C<bin>, C<sys> etc) rather than -simply by root. - -This is required since on many unix systems C</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 C<safe_level> is set to MEDIUM or higher. - -=back - -=cut - -{ - my $TopSystemUID = 10; - sub top_system_uid { - my $self = shift; - if (@_) { - my $newuid = shift; - croak "top_system_uid: UIDs should be numeric" - unless $newuid =~ /^\d+$/s; - $TopSystemUID = $newuid; - } - return $TopSystemUID; - } -} - -=head1 WARNING - -For maximum security, endeavour always to avoid ever looking at, -touching, or even imputing the existence of the filename. You do not -know that that filename is connected to the same file as the handle -you have, and attempts to check this can only trigger more race -conditions. It's far more secure to use the filehandle alone and -dispense with the filename altogether. - -If you need to pass the handle to something that expects a filename -then, on a unix system, use C<"/dev/fd/" . fileno($fh)> for arbitrary -programs, or more generally C<< "+<=&" . fileno($fh) >> for Perl -programs. You will have to clear the close-on-exec bit on that file -descriptor before passing it to another process. - - use Fcntl qw/F_SETFD F_GETFD/; - fcntl($tmpfh, F_SETFD, 0) - or die "Can't clear close-on-exec flag on temp fh: $!\n"; - -=head2 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. - -=head1 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. - -=head1 SEE ALSO - -L<POSIX/tmpnam>, L<POSIX/tmpfile>, L<File::Spec>, L<File::Path> - -See L<IO::File> and L<File::MkTemp> for different implementations of -temporary file handling. - -=head1 AUTHOR - -Tim Jenness E<lt>t.jenness@jach.hawaii.eduE<gt> - -Copyright (C) 1999-2001 Tim Jenness and the UK Particle Physics and -Astronomy Research Council. All Rights Reserved. This program is free -software; you can redistribute it and/or modify it under the same -terms as Perl itself. - -Original Perl implementation loosely based on the OpenBSD C code for -mkstemp(). Thanks to Tom Christiansen for suggesting that this module -should be written and providing ideas for code improvements and -security enhancements. - -=cut - - -1; |
