fig13_18.pl

来自「PERL语言资料 可以用于PERL程序设计」· PL 代码 · 共 50 行

#!/usr/bin/perl
# Figure 13.18: fig13_18.pl
# Passing filehandles to functions

use warnings;
use strict;

my $file = shift( @ARGV );
open( FILE, $file ) or die( "Error opening $file: $!" );
my $filehandle = *FILE;
readhandle( $filehandle );
close( FILE ) or die( "Error closing $file: $!" );

print( "\n\nNow a 2nd time...\n" );
open( FILE, $file ) or die( "Error opening $file: $!" );
$filehandle = \*FILE;
readhandle( $filehandle );
close( FILE ) or die( "Error closing $file: $!" );

print( "\n\nAnd finally...\n" );
readfile( $file );

sub readhandle
{
   my $fh = shift();
   print while ( <$fh> );
}

sub readfile
{
   my $file = shift();
   local *FILE;
   open( FILE, $file ) or die( "Error opening $file: $!" );
   print while ( <FILE> );
}

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