On May 20, 2007, at 12:43 AM, Russell L. Harris wrote:
>> my $file_as_string = do {
>> open( my $fh, $filename ) or die "Can't open $filename: $!";
>> local $/ = undef;
>> <$fh>;
>> };
>
> I am confused by the use of "my $fh" in the open command. By what
> mechanism is $fd assigned a value?
The "my $fh" declares a lexical scalar, and the open() assigns a
filehandle to it.
The old way:
open( FILEHANDLE, $filename )
The new way:
open( my $fh, '<', $filename )
The problem with the old FILEHANDLE method is that it's a global
variable. It has no scope. If call a subroutine that also operates
on FILEHANDLE, say by closing the file, and then return, you're going
to be sad.
Lexical filehandles let you keep filehandles within a scope, where
they belong. When they go out of scope, they're automatically
closed, too.
Also, start using the 3-arg open. The middle argument gives an
explicit instruction on how to open the file, for input or output.
xoxo,
Andy
--
Andy Lester => [EMAIL PROTECTED] => www.petdance.com => AIM:petdance
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