Perl Writing to a file and Reading a file program.

Writing to a file

#!/usr/bin/perl

use strict;

use warnings;

use Path::Class;

use autodie; # die if problem reading or writing a file

my $dir = dir("/tmp"); # /tmp

my $file = $dir->file("file.txt"); # /tmp/file.txt

# Get a file_handle (IO::File object) you can write to

my $file_handle = $file->openw();

my @list = ('a', 'list', 'of', 'lines');

foreach my $line ( @list ) {

    # Add the line to the file

    $file_handle->print($line . "\n");

}

Appending to a file

# As above but use open('>>') instead of openw()

my $file_handle = $file->open('>>');

Reading a file

#!/usr/bin/perl

use strict;

use warnings;

use Path::Class;

use autodie; # die if problem reading or writing a file

my $dir = dir("/tmp"); # /tmp

my $file = $dir->file("file.txt");

# Read in the entire contents of a file

my $content = $file->slurp();

# openr() returns an IO::File object to read from

my $file_handle = $file->openr();

# Read in line at a time

while( my $line = $file_handle->getline() ) {

        print $line;

}

Path::Class makes working with directories (Path::Class::Dir) and files (Path::Class::File) clean and easy to do. Try to work with file() or dir() objects throughout your code, but remember if you are calling other Perl modules you will often need to convert the object to a string using 'stringify':

    $file->stringify();

    $dir->stringify();