file::temp.3

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.\" ========================================================================
.\"
.IX Title "Temp 3"
.TH Temp 3 "2007-12-21" "perl v5.10.0" "User Contributed Perl Documentation"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH "NAME"
File::Temp \- return name and handle of a temporary file safely
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\&  use File::Temp qw/ tempfile tempdir /;
\&
\&  $fh = tempfile();
\&  ($fh, $filename) = tempfile();
\&
\&  ($fh, $filename) = tempfile( $template, DIR => $dir);
\&  ($fh, $filename) = tempfile( $template, SUFFIX => \*(Aq.dat\*(Aq);
\&  ($fh, $filename) = tempfile( $template, TMPDIR => 1 );
\&
\&  binmode( $fh, ":utf8" );
\&
\&  $dir = tempdir( CLEANUP => 1 );
\&  ($fh, $filename) = tempfile( DIR => $dir );
.Ve
.PP
Object interface:
.PP
.Vb 3
\&  require File::Temp;
\&  use File::Temp ();
\&  use File::Temp qw/ :seekable /;
\&
\&  $fh = File::Temp\->new();
\&  $fname = $fh\->filename;
\&
\&  $fh = File::Temp\->new(TEMPLATE => $template);
\&  $fname = $fh\->filename;
\&
\&  $tmp = File::Temp\->new( UNLINK => 0, SUFFIX => \*(Aq.dat\*(Aq );
\&  print $tmp "Some data\en";
\&  print "Filename is $tmp\en";
\&  $tmp\->seek( 0, SEEK_END );
.Ve
.PP
The following interfaces are provided for compatibility with
existing APIs. They should not be used in new code.
.PP
MkTemp family:
.PP
.Vb 1
\&  use File::Temp qw/ :mktemp  /;
\&
\&  ($fh, $file) = mkstemp( "tmpfileXXXXX" );
\&  ($fh, $file) = mkstemps( "tmpfileXXXXXX", $suffix);
\&
\&  $tmpdir = mkdtemp( $template );
\&
\&  $unopened_file = mktemp( $template );
.Ve
.PP
\&\s-1POSIX\s0 functions:
.PP
.Vb 1
\&  use File::Temp qw/ :POSIX /;
\&
\&  $file = tmpnam();
\&  $fh = tmpfile();
\&
\&  ($fh, $file) = tmpnam();
.Ve
.PP
Compatibility functions:
.PP
.Vb 1
\&  $unopened_file = File::Temp::tempnam( $dir, $pfx );
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\f(CW\*(C`File::Temp\*(C'\fR 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 \fItempfile()\fR function can
be used to return the name and the open filehandle of a temporary
file.  The \fItempdir()\fR function can be used to create a temporary
directory.
.PP
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\*(R" for more information.
.PP
For compatibility with popular C library functions, Perl implementations of
the \fImkstemp()\fR family of functions are provided. These are, \fImkstemp()\fR,
\&\fImkstemps()\fR, \fImkdtemp()\fR and \fImktemp()\fR.
.PP
Additionally, implementations of the standard \s-1POSIX\s0
\&\fItmpnam()\fR and \fItmpfile()\fR functions are provided if required.
.PP
Implementations of \fImktemp()\fR, \fItmpnam()\fR, and \fItempnam()\fR 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.
.PP
Filehandles returned by these functions support the seekable methods.
.SH "OBJECT-ORIENTED INTERFACE"
.IX Header "OBJECT-ORIENTED INTERFACE"
This is the primary interface for interacting with
\&\f(CW\*(C`File::Temp\*(C'\fR. Using the \s-1OO\s0 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.
.PP
Note that there is no method to obtain the filehandle from the
\&\f(CW\*(C`File::Temp\*(C'\fR object. The object itself acts as a filehandle. Also,
the object is configured such that it stringifies to the name of the
temporary file, and can be compared to a filename directly. The object
isa \f(CW\*(C`IO::Handle\*(C'\fR and isa \f(CW\*(C`IO::Seekable\*(C'\fR so all those methods are
available.
.IP "\fBnew\fR" 4
.IX Item "new"
Create a temporary file object.
.Sp
.Vb 1
\&  my $tmp = File::Temp\->new();
.Ve
.Sp
by default the object is constructed as if \f(CW\*(C`tempfile\*(C'\fR
was called without options, but with the additional behaviour
that the temporary file is removed by the object destructor
if \s-1UNLINK\s0 is set to true (the default).
.Sp
Supported arguments are the same as for \f(CW\*(C`tempfile\*(C'\fR: \s-1UNLINK\s0
(defaulting to true), \s-1DIR\s0, \s-1EXLOCK\s0 and \s-1SUFFIX\s0. Additionally, the filename
template is specified using the \s-1TEMPLATE\s0 option. The \s-1OPEN\s0 option
is not supported (the file is always opened).
.Sp
.Vb 3
\& $tmp = File::Temp\->new( TEMPLATE => \*(AqtempXXXXX\*(Aq,
\&                        DIR => \*(Aqmydir\*(Aq,
\&                        SUFFIX => \*(Aq.dat\*(Aq);
.Ve
.Sp
Arguments are case insensitive.
.Sp
Can call \fIcroak()\fR if an error occurs.
.IP "\fBnewdir\fR" 4
.IX Item "newdir"
Create a temporary directory using an object oriented interface.
.Sp
.Vb 1
\&  $dir = File::Temp\->newdir();
.Ve
.Sp
By default the directory is deleted when the object goes out of scope.
.Sp
Supports the same options as the \f(CW\*(C`tempdir\*(C'\fR function. Note that directories
created with this method default to \s-1CLEANUP\s0 => 1.
.Sp
.Vb 1
\&  $dir = File::Temp\->newdir( $template, %options );
.Ve
.IP "\fBfilename\fR" 4
.IX Item "filename"
Return the name of the temporary file associated with this object
(if the object was created using the \*(L"new\*(R" constructor).
.Sp
.Vb 1
\&  $filename = $tmp\->filename;
.Ve
.Sp
This method is called automatically when the object is used as
a string.
.IP "\fBdirname\fR" 4
.IX Item "dirname"
Return the name of the temporary directory associated with this
object (if the object was created using the \*(L"newdir\*(R" constructor).
.Sp
.Vb 1
\&  $dirname = $tmpdir\->dirname;
.Ve
.Sp
This method is called automatically when the object is used in string context.
.IP "\fBunlink_on_destroy\fR" 4
.IX Item "unlink_on_destroy"
Control whether the file is unlinked when the object goes out of scope.
The file is removed if this value is true and \f(CW$KEEP_ALL\fR is not.
.Sp
.Vb 1
\& $fh\->unlink_on_destroy( 1 );
.Ve
.Sp
Default is for the file to be removed.
.IP "\fB\s-1DESTROY\s0\fR" 4