Perl command?

Question

$dir = "/folder1/folder2/folder3"; >> Problem 1

if(opendir(DIR,$dir)) {

foreach my $filename (readdir DIR) {

if($filename =~ /*.xml$/i) { >> Problem 2

if(open(Open_Input,"$dir/$filename")) {

#do whatever you want

I'm new in perl and have 2 problems with the above code. What i want is to open specific folders and searh for all the xml files. However in Problem1 the folder names changes for example folder2 may sometimes be folder8 or folder10 so i can't specify a fixed folder. Also I get an error in Problem 2 for searhing all the xml files in a folder please help???

Answer 1

If you want to write the program yourself, that first bit would be best to write as a recursive function, as suggested.  Something like:

my(@xml_files) = find_xml("/base_folder");

sub find_xml {

  my($dir) = @_;

  return undef unless(-d $dir); #skip things that aren't valid dirs

  return undef unless(opendir(XML_DIR,$dir)); #skip things you can't open

  my(@xml_files) = ();

  foreach my $file (readdir(XML_DIR)) {

    next if($file =~ /^\.\.?$/); #don't get stuck in a loop or go backwards up the dir tree

    if(-d "$dir/$file") {

      push @xml_files,find_xml("$dir/$file");

    } elsif(-f "$dir/$file" && $file =~ /\.xml$/i) {

      push @xml_files, "$dir/$file";

    }

  }

  return @xml_files;

}

In problem 2, your regex is incorrect-- the asterisk must follow a character.  In this case, you want it to be:

/.*.xml$/i

But even that's not completely correct, because the filename "ilove.myxml" would match, when you probably don't want it to.  Instead, because the "." is a single character wildcard, and you probably mean the literal character, you really want:

/.*\.xml$/i

But even that is kind of extraneous, because the ".*" will match anything or nothing.  So you might as well just say:

/\.xml$/i

(Note that's the regex I used in my example)

DaveE

Answer 2

You need to use RECURSION to look into folders and subfolders.  Hint: write a function that takes a path name, tests whether it's a folder or a file, and does the right thing accordingly.

You could also use the File::Find module which does all this for you.