$fh = tempfile();
+Object interface:
+
+ require File::Temp;
+ use File::Temp ();
+
+ $fh = new File::Temp($template);
+ $fname = $fh->filename;
+
+ $tmp = new File::Temp( UNLINK => 0, SUFFIX => '.dat' );
+ print $tmp "Some data\n";
+ print "Filename is $tmp\n";
+
+
MkTemp family:
use File::Temp qw/ :mktemp /;
$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.
+C<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
# Need the Symbol package if we are running older perl
require Symbol if $] < 5.006;
+### For the OO interface
+use base qw/ IO::Handle /;
+use overload '""' => "STRINGIFY";
+
# use 'our' on v5.6.0
use vars qw($VERSION @EXPORT_OK %EXPORT_TAGS $DEBUG);
# Version number
-$VERSION = '0.131';
+$VERSION = '0.14';
# This is a list of characters that can be used in random filenames
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' || $^O eq 'MacOS') {
+ if ( $^O eq 'MSWin32' || $^O eq 'os2' || $^O eq 'cygwin' || $^O eq 'dos' || $^O eq 'MacOS' || $^O eq 'mpeix') {
return 0;
} else {
return 1;
}
+=head1 OO INTERFACE
+
+This is the primary interface for interacting with
+C<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
+C<File::Temp> object. The object itself acts as a filehandle. Also,
+the object is configured such that it stringifies to the name of the
+temporary file.
+
+=over 4
+
+=item B<new>
+
+Create a temporary file object.
+
+ my $tmp = new File::Temp();
+
+by default the object is constructed as if C<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 C<tempfile>: UNLINK
+(defaulting to true), DIR and SUFFIX. Additionally, the filename
+template is specified using the TEMPLATE option. The OPEN option
+is not supported (the file is always opened).
+
+ $tmp = new File::Temp( TEMPLATE => 'tempXXXXX',
+ DIR => 'mydir',
+ SUFFIX => '.dat');
+
+Arguments are case insensitive.
+
+=cut
+
+sub new {
+ my $proto = shift;
+ my $class = ref($proto) || $proto;
+
+ # read arguments and convert keys to upper case
+ my %args = @_;
+ %args = map { uc($_), $args{$_} } keys %args;
+
+ # see if they are unlinking (defaulting to yes)
+ my $unlink = (exists $args{UNLINK} ? $args{UNLINK} : 1 );
+ delete $args{UNLINK};
+
+ # template (store it in an error so that it will
+ # disappear from the arg list of tempfile
+ my @template = ( exists $args{TEMPLATE} ? $args{TEMPLATE} : () );
+ delete $args{TEMPLATE};
+
+ # Protect OPEN
+ delete $args{OPEN};
+
+ # Open the file and retain file handle and file name
+ my ($fh, $path) = tempfile( @template, %args );
+
+ print "Tmp: $fh - $path\n" if $DEBUG;
+
+ # Store the filename in the scalar slot
+ ${*$fh} = $path;
+
+ # Store unlink information in hash slot (plus other constructor info)
+ %{*$fh} = %args;
+ ${*$fh}{UNLINK} = $unlink;
+
+ bless $fh, $class;
+
+ return $fh;
+}
+
+=item B<filename>
+
+Return the name of the temporary file associated with this object.
+
+ $filename = $tmp->filename;
+
+This method is called automatically when the object is used as
+a string.
+
+=cut
+
+sub filename {
+ my $self = shift;
+ return ${*$self};
+}
+
+sub STRINGIFY {
+ my $self = shift;
+ return $self->filename;
+}
+
+=item B<DESTROY>
+
+When the object goes out of scope, the destructor is called. This
+destructor will attempt to unlink the file (using C<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.
+
+=cut
+
+sub DESTROY {
+ my $self = shift;
+ if (${*$self}{UNLINK}) {
+ print "# ---------> Unlinking $self\n" if $DEBUG;
+
+ # The unlink1 may fail if the file has been closed
+ # by the caller. This leaves us with the decision
+ # of whether to refuse to remove the file or simply
+ # do an unlink without test. Seems to be silly
+ # to do this when we are trying to be careful
+ # about security
+ unlink1( $self, $self->filename )
+ or unlink($self->filename);
+ }
+}
+
+=back
+
=head1 FUNCTIONS
This section describes the recommended interface for generating
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.
+at the end of the template.
($fh, $filename) = tempfile($template, SUFFIX => $suffix)
have a filehandle, you can never create a race condition
by fumbling with the filename. On systems that can not unlink
an open file or can not mark a file as temporary when it is opened
-(for example, Windows NT uses the C<O_TEMPORARY> flag))
+(for example, Windows NT uses the C<O_TEMPORARY> flag)
the file is marked for deletion when the program ends (equivalent
to setting UNLINK to 1). The C<UNLINK> flag is ignored if present.
# Read args
my ($fh, $path) = @_;
- warn "Unlinking $path using unlink0\n"
+ cmpstat($fh, $path) or 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
+ my @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, $path, 0);
+ return 1;
+ }
+
+}
+
+=item B<cmpstat>
+
+Compare C<stat> of filehandle with C<stat> of provided filename. This
+can be used to check that the filename and filehandle initially point
+to the same file and that the number of links to the file is 1 (all
+fields returned by stat() are compared).
+
+ cmpstat($fh, $path) or die "Error comparing handle with file";
+
+Returns false if the stat information differs or if the link count is
+greater than 1.
+
+On certain platofms, eg Windows, not all the fields returned by stat()
+can be compared. For example, the C<dev> and C<rdev> fields seem to be
+different in Windows. Also, it seems that the size of the file
+returned by stat() does not always agree, with C<stat(FH)> being more
+accurate than C<stat(filename)>, presumably because of caching issues
+even when using autoflush (this is usually overcome by waiting a while
+after writing to the tempfile before attempting to C<unlink0> it).
+
+Not exported by default.
+
+=cut
+
+sub cmpstat {
+
+ croak 'Usage: cmpstat(filehandle, filename)'
+ unless scalar(@_) == 2;
+
+ # Read args
+ my ($fh, $path) = @_;
+
+ warn "Comparing stat\n"
if $DEBUG;
- # Stat the filehandle
- my @fh = stat $fh;
+ # Stat the filehandle - which may be closed if someone has manually
+ # closed the file. Can not turn off warnings without using $^W
+ # unless we upgrade to 5.006 minimum requirement
+ my @fh;
+ {
+ local ($^W) = 0;
+ @fh = stat $fh;
+ }
+ return unless @fh;
if ($fh[3] > 1 && $^W) {
carp "unlink0: fstat found too many links; SB=@fh" if $^W;
} elsif ($^O eq 'VMS') { # device and file ID are sufficient
@okstat = (0, 1);
} elsif ($^O eq 'dos') {
- @okstat = (0,2..7,11..$#fh);
+ @okstat = (0,2..7,11..$#fh);
+ } elsif ($^O eq 'mpeix') {
+ @okstat = (0..4,8..10);
}
# Now compare each entry explicitly by number
}
}
- # 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;
+ return 1;
+}
- # Stat the filehandle
- @fh = stat $fh;
+=item B<unlink1>
- print "Link count = $fh[3] \n" if $DEBUG;
+Similar to C<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 C<unlink0> is not available.
- # 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 $^O eq 'cygwin' ? 1 : 0);
+ unlink1($fh, $path) or die "Error closing and unlinking file";
- } else {
- _deferred_unlink($fh, $path, 0);
- return 1;
- }
+Usually called from the object destructor when using the OO interface.
+
+Not exported by default.
+
+=cut
+sub unlink1 {
+ croak 'Usage: unlink1(filehandle, filename)'
+ unless scalar(@_) == 2;
+
+ # Read args
+ my ($fh, $path) = @_;
+
+ cmpstat($fh, $path) or return 0;
+
+ # Close the file
+ close( $fh ) or return 0;
+
+ # remove the file
+ return unlink($path);
}
=back
=cut
-
1;
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