in reply to symbolic links

my @array = grep { -T "$dir/$_" } readdir BIN;

your  grep { -T "$dir/$_" } selects everything that appears to be a text file. If your executable is a compiled program (i.e. not an executable script) it's probably getting filtered out.

If you want to link to every file, you can use grep { -f "$dir/$_" }.

See also -X and grep.

As an aside, I strongly recommend you use strict at the top of every script. It'll catch a lot of errors at compile time that might otherwise become hard to locate bugs. For your script to work with strict, you need to declare $file, like so: 

# ...
foreach my $file (@array) { 
# ...

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"What should it profit a man, if he should win a flame war, yet lose his cool?"

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Re^2: symbolic links
by garu (Scribe) on Jun 26, 2007 at 00:41 UTC
    As Joost++ points out, the problem in your code is that it checks only for text files (-T), hence not including your executable binary.

    Also, if you're trying to create the link on the parent directory, the destination string should read "/home/test/", not "/home/folder" (you should probably not hardcode it like that either, as any typo can bring unexpected bugs like this one. Use you $dir variable! :-)

    But what I would really warn you about is on putting the returned value of symlink() back on $file. Not only it destroys your filename for further use, the variable name differing from what it actually does (or any multi-use variable at any rate) will most likely confuse you if your program escalates.

    Even worse, if a user tries to run your program on a filesystem that does not support symbolic links, it will cause a fatal error unless you trap it in an eval block. You could do something like: 

    #!/usr/bin/perl
use strict;
use warnings;

my $dir = "/home/test/folder";
opendir(BIN, $dir) or die "Can't open $dir: $!\n";
my @array = grep { -f "$dir/$_" } readdir BIN;

foreach my $file (@array) {
   eval { symlink ("$dir/$file","$dir/../$file") }; # links to parent
   if ($@) {
      print "could not create symlink for $file\n";
   }
   else {
      print "success!\n";
   }
}

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    Of course, if this is just a simple PoC code where you were not particularly concerned with the pointed issues, feel free to ignore them :-)

    Hope this helps!

[reply]
[d/l]
      Hi Hope you don’t mind but I have another question. I have been playing around with the script the only thing I’m having trouble with now is that I have tried to create a symbolic link to an ordinary file as well as a binary but can seem to link to a folder. Any thoughts or suggestions would be greatly received. Thanks for all your help.
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