I have been looking through the code for this module to see if anything jumps out at me. Based on what you describe and the information in the linked trouble ticket, I wondered if there might be a race condition between the send and read subroutines.

So far I have identified only one unrelated bug in the Linux.pm code (I realize you are working with WinXP) but this prevented building the module on my linux box. Line 98 of Linux.pm should be: 

 $this->{START_CMD} = "$this->{R_BIN} --slave --vanilla" ;

[download]

The original included a "--gui=none" option that has been deprecated in the most recent versions of R>=2.1.

In any case, I will continue to plod through the send and read subroutines to see if I can find something useful. I will also post the code here with the hope that someone with a better endogenous perl parser can suggest a test or fix faster.

Here is the send subroutine from pipe.pm: 

  sub send { 
    my $CLASS_HPLOO ;
    $CLASS_HPLOO = $this if defined $this ;
    my $this = UNIVERSAL::isa($_[0],'UNIVERSAL') ? shift : $CLASS_HPLO
+O ;
    my $class = ref($this) || __PACKAGE__ ;
    $CLASS_HPLOO = undef ;
    my $cmd = shift(@_) ;
    
    $cmd =~ s/\r\n?/\n/gs ;
    $cmd .= "\n" if $cmd !~ /\n$/ ;
    $cmd =~ s/\n/\r\n/gs ;
    
    while ( $this->is_blocked ) { sleep(1) ;}
    
    my $n = $this->read_processR ;
    $n = 1 if $n eq '0' || $n eq '' ;
    
    my $file = "$this->{LOG_DIR}/input.$n.r" ;
    
    while( -e $file || -e "$file._" ) {
      ++$n ;
      $file = "$this->{LOG_DIR}/input.$n.r" ;
    }

    open (my $fh,">$file._") ;
    print $fh "$cmd\n" ;
    close ($fh) ;
    
    chmod(0777 , "$file._") ;
    
    $this->{OUTPUT_R_POS} = -s $this->{OUTPUT_R} ;
    
    rename("$file._" , $file) ;
    
    my $has_quit = 1 if $cmd =~ /^\s*(?:q|quit)\s*\(.*?\)\s*$/s ;
    
    ##print "CMD[$n]$has_quit>> $cmd\n" ;
    
    my $status = 1 ;
    my $delay = 0.02 ;
    
    my ($x,$xx) ;
    while( (!$has_quit || $this->{STOPING} == 1) && -e $file && $this-
+>is_started( !$this->{STOPING} ) ) {
      ++$x ;
      ##print "sleep $file\n" ;
      select(undef,undef,undef,$delay) ;
      if ( $x == 20 ) {
        my (undef , $data) = $this->read_processR ;
        if ( $data =~ /\s$n\s+\.\.\.\s+\// ) { last ;}
        $x = 0 ;
        ++$xx ;
        $delay = 0.5 ;
      }
      if ( $xx > 5 ) { $status = undef ;} ## xx > 5 = x > 50
    }
    
    if ( $has_quit && !$this->{STOPING} ) { $this->stop(1) ;}

    return $status ;
  }

[download]

and here is the read subroutine from pipe.pm. 

  sub read { 
    my $CLASS_HPLOO ;
    $CLASS_HPLOO = $this if defined $this ;
    my $this = UNIVERSAL::isa($_[0],'UNIVERSAL') ? shift : $CLASS_HPLO
+O ;
    my $class = ref($this) || __PACKAGE__ ;
    $CLASS_HPLOO = undef ;
    my $timeout = shift(@_) ;
    
    $timeout = -1 if $timeout eq '' ;
    
    open (my $fh, $this->{OUTPUT_R} ) ; binmode($fh) ;
    seek($fh , ($this->{OUTPUT_R_POS}||0) , 0) ;
    
    my $time = time ;
    my ($x,$data) ;

    while( $x == 0 || (time-$time) <= $timeout ) {
      ++$x ;
      my $s = -s $this->{OUTPUT_R} ;
      my $r = read($fh , $data , ($s - $this->{OUTPUT_R_POS}) , length
+($data) ) ;
      $this->{OUTPUT_R_POS} = tell($fh) ;
      last if !$r ;
    }
    
    close($fh) ;
    
    my @lines = split(/(?:\r\n?|\n)/s , $data) ;
    
    return @lines if wantarray ;
    return join("\n", @lines) ;
  }

[download]

In reply to Re: Buggy CPAN Module (Statistics::R) by moklevat
in thread Buggy CPAN Module (Statistics::R) by maybeD

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