in reply to Re: Problems with Filehandles and TeeOutput
in thread Problems with Filehandles and TeeOutput

OK, here is the results of my testing: 
#Works
local *LOG;
open(LOG, '>>test.out');
openTee(*STDOUT, *STDOUT, *LOG); 

#Does not work
my $fh = IO::File->new(">>test.out");
openTee(*STDOUT, *STDOUT, *$fh);

#Does not work
open(my $fh, '>>', 'test.out');
openTee(*STDOUT, *STDOUT, *$fh);

#Does not work
open(my $fh, '>>', 'test.out');
openTee(*STDOUT, *STDOUT, *$fh);

#Works
openTee(*STDOUT, *STDOUT, '>>test.out');

#Works
openTee(*STDOUT, *STDOUT, 'test.out');

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Note the resason I am using IO::File is because actually I want to use IO::File->new_tmpfile, but as that doesn't work I am trying IO::File->new to make testing easier. Note the only reason I was trying to get new_tmpfile working was cause I couldn't get it into a string using scalar I/O 
open($fh, "+<", \$string);

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Re^3: Problems with Filehandles and TeeOutput
by ikegami (Patriarch) on Aug 26, 2008 at 05:56 UTC
    Sorry, but the module you are using wasn't written to work on lexical handles, introduced over 8 years ago with 5.6.

    Update: IO::Tee appears to work with lexical file handles as well.

[reply]
      Thanks, IO::Tee gets me a little bit closer 
      #!/usr/bin/perl -w
use strict;
use warnings;
use IO::Tee;
use IO::File;

my $stdout;
open(my $fh, "+<", \$stdout); 
my $tee = new IO::Tee(\*STDOUT, $fh);
print $tee `echo Test`;
print $stdout;

      [download]
      However I am actually trying to capture STDERR, so this code isn't that useful to me. I have tried IO::CaptureOutput but I can't get that working. Note apologies, as I know that this (capturing STDERR to local variable as well as directing to file) has been covered many times before perlmonks and elsewhere, but I haven't come across a definitive solution - I was hoping that TeeOutput would be the answer, I guess not.
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[d/l]

        However I am actually trying to capture STDERR, so this code isn't that useful to me.

        You can't pass the file handles created by Tee modules to child processes since they don't correspond to system file handles, and neither is the file handle returned by open \$var.

        You should probably start a new thread and state your actual problem. I could try to come up with an answer, but you'd benefit from starting over because 1) the question hasn't fully been revealed, and 2) you'd get more answers than just my own.

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[d/l]
Re^3: Problems with Filehandles and TeeOutput
by massa (Hermit) on Aug 26, 2008 at 09:41 UTC
    I couldn't help but notice that you used 
    #Does not work
open(my $fh, '>>', 'test.out');
openTee(*STDOUT, *STDOUT, *$fh);

    [download]
    instead of
    #Should be working
open(my $fh, '>>', 'test.out');
openTee(*STDOUT, *STDOUT, $fh);
#asterisks ONLY before STDOUT, NOT $fh

    [download]
    would you mind testing once more?
    []s, HTH, Massa (κς,πμ,πλ)
[reply]
[d/l]
[select]

      That was intentional. It definitely won't work without the asterisk because the module expects a glob, not a reference to one. 

      >perl -le"open(my $fh,'>','foo'); print( (ref(\$fh) eq 'GLOB') ?1:0)"
0

      [download]

      That needs to be 1 or that module will stringify the handle.

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[d/l]
      Tested, still not working. 
      #!/usr/bin/perl -w
use Local::TeeOutput;
use strict;
#No, still not working...
open(my $fh, '>>', 'test2.out'); 
openTee(*STDOUT, *STDOUT, $fh); 
print "XX\n";
close($fh);

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      Note it creates a file called GLOB(0x239bcc) which contains the correct data. Note I have been further reading simlar threads on perlmonks and elsewhere for what I am actually trying to do (write STDERR to file and save as variable). The solutions I have found are very complicated and work only on Unix (mine needs to be windows and unix compatible). Coming to the conclusion that the solution, if it exists will be take considerable effort which is likely not worthwile. I was hoping TeeOutput would be a quick solution, but it looks like it won't be suitable.
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[d/l]

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