Bio::Root
IO
Toolbar
Summary
Bio::Root::IO - module providing several methods often needed when dealing with file IO
Package variables
Privates (from "my" definitions)
$HAS_WIN32 = 0
$TEMPCOUNTER;
Included modules
IO::Handle
POSIX qw ( dup )
Symbol
Inherit
Synopsis
# utilize stream I/O in your module
$self->{'io'} = Bio::Root::IO->new(-file => "myfile");
$self->{'io'}->_print("some stuff");
$line = $self->{'io'}->_readline();
$self->{'io'}->_pushback($line);
$self->{'io'}->close();
# obtain platform-compatible filenames
$path = Bio::Root::IO->catfile($dir, $subdir, $filename);
# obtain a temporary file (created in $TEMPDIR)
($handle) = $io->tempfile();
Description
This module provides methods that will usually be needed for any sort
of file- or stream-related input/output, e.g., keeping track of a file
handle, transient printing and reading from the file handle, a close
method, automatically closing the handle on garbage collection, etc.
To use this for your own code you will either want to inherit from
this module, or instantiate an object for every file or stream you are
dealing with. In the first case this module will most likely not be
the first class off which your class inherits; therefore you need to
call _initialize_io() with the named parameters in order to set file
handle, open file, etc automatically.
Most methods start with an underscore, indicating they are private. In
OO speak, they are not private but protected, that is, use them in
your module code, but a client code of your module will usually not
want to call them (except those not starting with an underscore).
In addition this module contains a couple of convenience methods for
cross-platform safe tempfile creation and similar tasks. There are
some CPAN modules related that may not be available on all
platforms. At present, File::Spec and File::Temp are attempted. This
module defines $PATHSEP, $TEMPDIR, and $ROOTDIR, which will always be set,
and $OPENFLAGS, which will be set if either of File::Spec or File::Temp fails.
The -noclose boolean (accessed via the noclose method) prevents a
filehandle from being closed when the IO object is cleaned up. This
is special behavior when a object like a parser might share a
filehandle with an object like an indexer where it is not proper to
close the filehandle as it will continue to be reused until the end of the
stream is reached. In general you won't want to play with this flag.
Methods
Methods description
Title : _fh Usage : $obj->_fh($newval) Function: Get/set the file handle for the stream encapsulated. Example : Returns : value of _filehandle Args : newvalue (optional) |
Title : _flush_on_write Usage : $obj->_flush_on_write($newval) Function: Boolean flag to indicate whether to flush the filehandle on writing when the end of a component is finished (Sequences,Alignments,etc) Returns : value of _flush_on_write Args : newvalue (optional) |
Title : initialize_io Usage : $self->_initialize_io(@params); Function: Initializes filehandle and other properties from the parameters.
Currently recognizes the following named parameters:
-file name of file to open
-input name of file, or GLOB, or IO::Handle object
-fh file handle (mutually exclusive with -file)
-flush boolean flag to autoflush after each write
-noclose boolean flag, when set to true will not close a
filehandle (must explictly call close($io->_fh)
Returns : TRUE
Args : named parameters |
Title : _print Usage : $obj->_print(@lines) Function: Example : Returns : writes output |
Title : _pushback Usage : $obj->_pushback($newvalue) Function: puts a line previously read with _readline back into a buffer. buffer can hold as many lines as system memory permits. Example : Returns : Args : newvalue |
Title : _readline Usage : $obj->_readline(%args) Function: Reads a line of input.
Note that this method implicitely uses the value of $/ that is
in effect when called.
Note also that the current implementation does not handle pushed
back input correctly unless the pushed back input ends with the
value of $/.
Example :
Args : Accepts a hash of arguments, currently only -raw is recognized
passing (-raw => 1) prevents \r\n sequences from being changed
to \n. The default value of -raw is undef, allowing \r\n to be
converted to \n.
Returns : |
Title : catfile Usage : $path = Bio::Root::IO->catfile(@dirs,$filename); Function: Constructs a full pathname in a cross-platform safe way.
If File::Spec exists on your system, this routine will merely
delegate to it. Otherwise it tries to make a good guess.
You should use this method whenever you construct a path name
from directory and filename. Otherwise you risk cross-platform
compatibility of your code.
You can call this method both as a class and an instance method.
Returns : a string
Args : components of the pathname (directories and filename, NOT an
extension) |
Title : close Usage : $io->close() Function: Closes the file handle associated with this IO instance. Will not close the FH if -noclose is specified Returns : none Args : none |
Title : exists_exe Usage : $exists = $obj->exists_exe('clustalw'); $exists = Bio::Root::IO->exists_exe('clustalw') $exists = Bio::Root::IO::exists_exe('clustalw') Function: Determines whether the given executable exists either as file or within the path environment. The latter requires File::Spec to be installed. On Win32-based system, .exe is automatically appended to the program name unless the program name already ends in .exe. Example : Returns : 1 if the given program is callable as an executable, and 0 otherwise Args : the name of the executable |
Title : file Usage : $obj->file($newval) Function: Get/set the filename, if one has been designated. Example : Returns : value of file Args : newvalue (optional) |
Title : flush Usage : $io->flush() Function: Flushes the filehandle Returns : none Args : none |
Title : mode Usage : $obj->mode() Function: Example : Returns : mode of filehandle: 'r' for readable 'w' for writeable '?' if mode could not be determined Args : -force (optional), see notes. Notes : once mode() has been called, the filehandle's mode is cached for further calls to mode(). to override this behavior so that mode() re-checks the filehandle's mode, call with arg -force |
Title : new Usage : Function: Overridden here to automatically call _initialize_io(). Example : Returns : new instance of this class Args : named parameters |
Title : noclose Usage : $obj->noclose($newval) Function: Get/Set the NOCLOSE flag - setting this to true will prevent a filehandle from being closed when an object is cleaned up or explicitly closed This is a bit of hack Returns : value of noclose (a scalar) Args : on set, new value (a scalar or undef, optional) |
Title : rmtree Usage : Bio::Root::IO->rmtree($dirname ); Function: Remove a full directory tree
If File::Path exists on your system, this routine will merely
delegate to it. Otherwise it runs a local version of that code.
You should use this method to remove directories which contain
files.
You can call this method both as a class and an instance method.
Returns : number of files successfully deleted
Args : roots - rootdir to delete or reference to list of dirs
verbose - a boolean value, which if TRUE will cause
rmtree to print a message each time it examines a file, giving the name of the file, and indicating whether it's using rmdir or unlink to remove it, or that it's skipping it. (defaults to FALSE)
safe - a boolean value, which if TRUE will cause rmtree to skip any files to which you do not have delete access (if running under VMS) or write access (if running under another OS). This will change in the future when a criterion for 'delete permission' under OSs other than VMS is settled. (defaults to FALSE) |
Title : tempdir Usage : my ($tempdir) = $io->tempdir(CLEANUP=>1); Function: Creates and returns the name of a new temporary directory.
Note that you should not use this function for obtaining "the"
temp directory. Use $Bio::Root::IO::TEMPDIR for that. Calling this
method will in fact create a new directory.
Returns : The name of a new temporary directory.
Args : args - ( key CLEANUP ) indicates whether or not to cleanup
dir on object destruction, other keys as specified by File::Temp |
Title : tempfile Usage : my ($handle,$tempfile) = $io->tempfile(); Function: Returns a temporary filename and a handle opened for writing and and reading.
Caveats : If you do not have File::Temp on your system you should avoid
specifying TEMPLATE and SUFFIX. (We don't want to recode
everything, okay?)
Returns : a 2-element array, consisting of temporary handle and temporary
file name
Args : named parameters compatible with File::Temp: DIR (defaults to
$Bio::Root::IO::TEMPDIR), TEMPLATE, SUFFIX. |
Methods code
BEGIN { $TEMPCOUNTER = 0;
$FILESPECLOADED = 0;
$FILETEMPLOADED = 0;
$FILEPATHLOADED = 0;
$VERBOSE = 1;
eval {
require File::Path;
$FILEPATHLOADED = 1;
};
if( $@ ) {
print STDERR "Cannot load File::Path: $@" if( $VERBOSE > 0 );
}
if($^O =~ /mswin/i) {
eval {
require Win32;
$HAS_WIN32 = 1;
};
}
if($^O =~ /mswin/i) {
$PATHSEP = "\\";
} elsif($^O =~ /macos/i) {
$PATHSEP = ":";
} else { $PATHSEP = "/";
}
eval {
require File::Spec;
$FILESPECLOADED = 1;
$TEMPDIR = File::Spec->tmpdir();
$ROOTDIR = File::Spec->rootdir();
require File::Temp; $FILETEMPLOADED = 1;
};
if( $@ ) {
if(! defined($TEMPDIR)) { if (defined $ENV{'TEMPDIR'} && -d $ENV{'TEMPDIR'} ) {
$TEMPDIR = $ENV{'TEMPDIR'};
} elsif( defined $ENV{'TMPDIR'} && -d $ENV{'TMPDIR'} ) {
$TEMPDIR = $ENV{'TMPDIR'};
}
if($^O =~ /mswin/i) {
$TEMPDIR = 'C:\TEMP' unless $TEMPDIR;
$ROOTDIR = 'C:';
} elsif($^O =~ /macos/i) {
$TEMPDIR = "" unless $TEMPDIR; $ROOTDIR = ""; } else { $TEMPDIR = "/tmp" unless $TEMPDIR;
$ROOTDIR = "/";
}
if (!( -d $TEMPDIR && -w $TEMPDIR )) {
$TEMPDIR = '.'; }
}
use Fcntl;
use Symbol;
$OPENFLAGS = O_CREAT | O_EXCL | O_RDWR;
for my $oflag (qw/FOLLOW BINARY LARGEFILE EXLOCK NOINHERIT TEMPORARY/){
my ($bit, $func) = (0, "Fcntl::O_" . $oflag);
no strict 'refs';
$OPENFLAGS |= $bit if eval { $bit = &$func(); 1 };
} } |
sub _fh
{ my ($obj, $value) = @_;
if ( defined $value) {
$obj->{'_filehandle'} = $value;
}
return $obj->{'_filehandle'}; } |
sub _flush_on_write
{ my ($self,$value) = @_;
if( defined $value) {
$self->{'_flush_on_write'} = $value;
}
return $self->{'_flush_on_write'};
}
1; } |
sub _initialize_io
{ my($self, @args) = @_;
$self->_register_for_cleanup(\&_io_cleanup);
my ($input, $noclose, $file, $fh, $flush) = $self->_rearrange([qw(INPUT
NOCLOSE
FILE FH
FLUSH)], @args);
delete $self->{'_readbuffer'};
delete $self->{'_filehandle'};
$self->noclose( $noclose) if defined $noclose;
if($input) {
if(ref(\$input) eq "SCALAR") {
if($file && ($file ne $input)) {
$self->throw("input file given twice: $file and $input disagree");
}
$file = $input;
} elsif(ref($input) &&
((ref($input) eq "GLOB") || $input->isa('IO::Handle'))) {
$fh = $input;
} else {
$self->throw("unable to determine type of input $input: ".
"not string and not GLOB");
}
}
if(defined($file) && defined($fh)) {
$self->throw("Providing both a file and a filehandle for reading - only one please!");
}
if(defined($file) && ($file ne '')) {
$fh = Symbol::gensym();
open ($fh,$file) ||
$self->throw("Could not open $file: $!");
$self->file($file);
}
$self->_fh($fh) if $fh;
$self->_flush_on_write(defined $flush ? $flush : 1);
return 1; } |
sub _io_cleanup
{ my ($self) = @_;
$self->close();
my $v = $self->verbose;
if( exists($self->{'_rootio_tempfiles'}) &&
ref($self->{'_rootio_tempfiles'}) =~ /array/i) {
if( $v > 0 ) {
print STDERR "going to remove files ",
join(",", @{$self->{'_rootio_tempfiles'}}), "\n";
}
unlink (@{$self->{'_rootio_tempfiles'}} );
}
if( $self->{'_cleanuptempdir'} &&
exists($self->{'_rootio_tempdirs'}) &&
ref($self->{'_rootio_tempdirs'}) =~ /array/i) {
if( $v > 0 ) {
print STDERR "going to remove dirs ",
join(",", @{$self->{'_rootio_tempdirs'}}), "\n";
}
$self->rmtree( $self->{'_rootio_tempdirs'});
} } |
sub _print
{ my $self = shift;
my $fh = $self->_fh() ||\* STDOUT;
print $fh @_; } |
sub _pushback
{ my ($obj, $value) = @_;
$obj->{'_readbuffer'} ||= [];
push @{$obj->{'_readbuffer'}}, $value; } |
sub _readline
{ my $self = shift;
my %param =@_;
my $fh = $self->_fh ||\* ARGV;
my $line;
$line = shift @{$self->{'_readbuffer'}} || <$fh>;
$line =~ s/\r\n/\n/g if( (!$param{-raw}) && (defined $line) );
return $line; } |
sub catfile
{ my ($self, @args) = @_;
return File::Spec->catfile(@args) if($FILESPECLOADED);
if($args[0] eq '/') {
$args[0] = $ROOTDIR;
}
return join($PATHSEP, @args); } |
sub close
{ my ($self) = @_;
return if $self->noclose; if( defined $self->{'_filehandle'} ) {
$self->flush;
return if(\* STDOUT == $self->_fh ||\*
STDERR == $self->_fh ||\*
STDIN == $self->_fh
); if( ! ref($self->{'_filehandle'}) ||
! $self->{'_filehandle'}->isa('IO::String') ) {
close($self->{'_filehandle'});
}
}
$self->{'_filehandle'} = undef;
delete $self->{'_readbuffer'}; } |
sub exists_exe
{ my ($self, $exe) = @_;
$exe = $self if(!(ref($self) || $exe));
$exe .= '.exe' if(($^O =~ /mswin/i) && ($exe !~ /\.(exe|com|bat|cmd)$/i));
return $exe if(-e $exe);
if($FILESPECLOADED) {
foreach my $dir (File::Spec->path()) {
my $f = Bio::Root::IO->catfile($dir, $exe);
return $f if(-e $f && -x $f );
}
}
return 0; } |
sub file
{ my ($obj, $value) = @_;
if ( defined $value) {
$obj->{'_file'} = $value;
}
return $obj->{'_file'}; } |
sub flush
{ my ($self) = shift;
if( !defined $self->{'_filehandle'} ) {
$self->throw("Attempting to call flush but no filehandle active");
}
if( ref($self->{'_filehandle'}) =~ /GLOB/ ) {
my $oldh = select($self->{'_filehandle'});
$| = 1;
select($oldh);
} else {
$self->{'_filehandle'}->flush();
} } |
sub mode
{ my ($obj, @arg) = @_;
my %param = @arg;
return $obj->{'_mode'} if defined $obj->{'_mode'} and !$param{-force};
print STDERR "testing mode... " if $obj->verbose;
my $fh = Symbol::gensym();
my $iotest = new IO::Handle;
$iotest->fdopen( dup(fileno($obj->_fh)) , 'r' );
if($iotest->error == 0){
if($^O eq 'linux'){
$obj->{'_mode'} = 'r';
my $line = $iotest->getline;
$obj->_pushback($line) if defined $line;
$obj->{'_mode'} = defined $line ? 'r' : 'w';
return $obj->{'_mode'};
} else {
my $line = $iotest->getline;
$obj->_pushback($line) if defined $line;
$obj->{'_mode'} = defined $line ? 'r' : 'w';
return $obj->{'_mode'};
}
}
$iotest->clearerr;
$iotest->fdopen( dup(fileno($obj->_fh)) , 'w' );
if($iotest->error == 0){
$obj->{'_mode'} = 'w';
}
return $obj->{'_mode'}; } |
sub new
{ my ($caller, @args) = @_;
my $self = $caller->SUPER::new(@args);
$self->_initialize_io(@args);
return $self; } |
sub noclose
{ my $self = shift;
return $self->{'_noclose'} = shift if @_;
return $self->{'_noclose'}; } |
sub rmtree
{ my($self,$roots, $verbose, $safe) = @_;
if( $FILEPATHLOADED ) {
return File::Path::rmtree ($roots, $verbose, $safe);
}
my $force_writeable = ($^O eq 'os2' || $^O eq 'dos' || $^O eq 'MSWin32'
|| $^O eq 'amigaos');
my $Is_VMS = $^O eq 'VMS';
my(@files);
my($count) = 0;
$verbose ||= 0;
$safe ||= 0;
if ( defined($roots) && length($roots) ) {
$roots = [$roots] unless ref $roots;
} else {
$self->warn("No root path(s) specified\n");
return 0;
}
my($root);
foreach $root (@{$roots}) {
$root =~ s#/\z##;
(undef, undef, my $rp) = lstat $root or next;
$rp &= 07777; if ( -d _ ) {
chmod(0777, ($Is_VMS ? VMS::Filespec::fileify($root) : $root))
or $self->warn("Can't make directory $root read+writeable: $!")
unless $safe;
if (opendir(DIR, $root) ){
@files = readdir DIR;
closedir(DIR);
} else {
$self->warn( "Can't read $root: $!");
@files = ();
}
@files = reverse @files if $Is_VMS;
($root = VMS::Filespec::unixify($root)) =~ s#\.dir\z## if $Is_VMS;
@files = map("$root/$_", grep $_!~/^\.{1,2}\z/s,@files);
$count += $self->rmtree([@files],$verbose,$safe);
if ($safe &&
($Is_VMS ? !&VMS::Filespec::candelete($root) : !-w $root)) {
print "skipped $root\n" if $verbose;
next;
}
chmod 0777, $root
or $self->warn( "Can't make directory $root writeable: $!")
if $force_writeable;
print "rmdir $root\n" if $verbose;
if (rmdir $root) {
++$count;
}
else {
$self->warn( "Can't remove directory $root: $!");
chmod($rp, ($Is_VMS ? VMS::Filespec::fileify($root) : $root))
or $self->warn("and can't restore permissions to "
. sprintf("0%o",$rp) . "\n");
}
}
else {
if ($safe &&
($Is_VMS ? !&VMS::Filespec::candelete($root)
: !(-l $root || -w $root)))
{
print "skipped $root\n" if $verbose;
next;
}
chmod 0666, $root
or $self->warn( "Can't make file $root writeable: $!")
if $force_writeable;
print "unlink $root\n" if $verbose;
for (;;) {
unless (unlink $root) {
$self->warn( "Can't unlink file $root: $!");
if ($force_writeable) {
chmod $rp, $root
or $self->warn("and can't restore permissions to "
. sprintf("0%o",$rp) . "\n");
}
last;
}
++$count;
last unless $Is_VMS && lstat $root;
}
}
}
$count; } |
sub tempdir
{ my ( $self, @args ) = @_;
if($FILETEMPLOADED && File::Temp->can('tempdir') ) {
return File::Temp::tempdir(@args);
}
my %params = @args;
$self->{'_cleanuptempdir'} = ( defined $params{CLEANUP} &&
$params{CLEANUP} == 1);
my $tdir = $self->catfile($TEMPDIR,
sprintf("dir_%s-%s-%s",
$ENV{USER} || 'unknown', $$,
$TEMPCOUNTER++));
mkdir($tdir, 0755);
push @{$self->{'_rootio_tempdirs'}}, $tdir;
return $tdir; } |
sub tempfile
{ my ($self, @args) = @_;
my ($tfh, $file);
my %params = @args;
foreach my $key (keys(%params)) {
if( $key =~ /^-/ ) {
my $v = $params{$key};
delete $params{$key};
$params{uc(substr($key,1))} = $v;
} else {
my $v = $params{$key};
delete $params{$key};
$params{uc($key)} = $v;
}
}
$params{'DIR'} = $TEMPDIR if(! exists($params{'DIR'}));
unless (exists $params{'UNLINK'} &&
defined $params{'UNLINK'} &&
! $params{'UNLINK'} ) {
$params{'UNLINK'} = 1;
} else { $params{'UNLINK'} = 0 }
if($FILETEMPLOADED) {
if(exists($params{'TEMPLATE'})) {
my $template = $params{'TEMPLATE'};
delete $params{'TEMPLATE'};
($tfh, $file) = File::Temp::tempfile($template, %params);
} else {
($tfh, $file) = File::Temp::tempfile(%params);
}
} else {
my $dir = $params{'DIR'};
$file = $self->catfile($dir,
(exists($params{'TEMPLATE'}) ?
$params{'TEMPLATE'} :
sprintf( "%s.%s.%s",
$ENV{USER} || 'unknown', $$,
$TEMPCOUNTER++)));
if( $HAS_WIN32 ) {
$file = Win32::GetShortPathName($file);
}
if ($] < 5.006) {
$tfh = &Symbol::gensym;
}
local $^F = 2;
my $umask = umask();
umask(066);
if ( sysopen($tfh, $file, $OPENFLAGS, 0600) ) {
umask($umask);
} else {
$self->throw("Could not open tempfile $file: $!\n");
}
}
if( $params{'UNLINK'} ) {
push @{$self->{'_rootio_tempfiles'}}, $file;
}
return wantarray ? ($tfh,$file) : $tfh; } |
General documentation
User feedback is an integral part of the evolution of this
and other Bioperl modules. Send your comments and suggestions preferably
to one of the Bioperl mailing lists.
Your participation is much appreciated.
bioperl-l@bioperl.org - General discussion
http://bio.perl.org/MailList.html - About the mailing lists
Report bugs to the Bioperl bug tracking system to help us keep track
the bugs and their resolution.
Bug reports can be submitted via email or the web:
bioperl-bugs@bio.perl.org
http://bugzilla.bioperl.org/
The rest of the documentation details each of the object methods. Internal methods are usually preceded with a _