filehandle to variable problem

[mathias]

Hello all,

i try to store filehandle in variable (as described in perl cookbook
for instance) and i am not able to use the variable afterwards.
instead of getting the expected content of the var, i get something
like *main::FH or main::STDOUT or GLOB(0x80f60ac)

you can see the sample script i use at:
http://www.tiasarea.org/perl.html
http://www.tiasarea.org/perl2.html
http://www.tiasarea.org/perl3.html

Thank you for any help

greetings

Mathias

 

[mathias]

: like *main::FH or main::STDOUT or GLOB(0x80f60ac)

It's a filehandle. Why do you care what it looks like when you print
its internal representation? What did you expect to happen?

Greg

well i was waiting for bla instead of any of the strings i had.
can you give me a way then to get "bla" from this filehandle ?

thank you
Mathias

 

[Jay Tilton]

: Greg Bacon wrote:
:
: > : like *main::FH or main::STDOUT or GLOB(0x80f60ac)
: >
: > It's a filehandle. Why do you care what it looks like when you print
: > its internal representation? What did you expect to happen?
: >
: > Greg

: well i was waiting for bla instead of any of the strings i had.
: can you give me a way then to get "bla" from this filehandle ?

Your code is short enough that including it in the article is
preferable to making readers go out to the web to see it.

[grabbed from http://www.tiasarea.org/perl.html]
#!/usr/bin/perl -w
use strict;

sub runme {
my $fh=shift;
print $fh "bla\n"; }

my $var;
open FH, '>', \$var;
runme(\*FH);
$var = *FH;
close FH;

print "var: \n";
print ">".$var."<\n";

the output from this script is:
var:

*main::FH<

In Perl 5.8.0, "open FH, '>', \$var" will cause stuff printed to FH to
go into $var. Cut out the "$var = *FH;" line and look in $var for
your 'bla'.

In an older Perl, that form of open() does not have the same behavior.
It just ends up stringifying the scalar reference, creating a file
named like "SCALAR(0x1a653b4)".

 

[mathias]

: Greg Bacon wrote:
:
: > : like *main::FH or main::STDOUT or GLOB(0x80f60ac)
: >
: > It's a filehandle. Why do you care what it looks like when you print
: > its internal representation? What did you expect to happen?
: >
: > Greg

: well i was waiting for bla instead of any of the strings i had.
: can you give me a way then to get "bla" from this filehandle ?

Your code is short enough that including it in the article is
preferable to making readers go out to the web to see it.

[grabbed from http://www.tiasarea.org/perl.html]
#!/usr/bin/perl -w
use strict;

sub runme {
my $fh=shift;
print $fh "bla\n"; }

my $var;
open FH, '>', \$var;
runme(\*FH);
$var = *FH;
close FH;

print "var: \n";
print ">".$var."<\n";

the output from this script is:
var:

*main::FH<

In Perl 5.8.0, "open FH, '>', \$var" will cause stuff printed to FH to
go into $var. Cut out the "$var = *FH;" line and look in $var for
your 'bla'.

In an older Perl, that form of open() does not have the same behavior.
It just ends up stringifying the scalar reference, creating a file
named like "SCALAR(0x1a653b4)".

thank you for the help
i finally solved it out

Mathias