Perl: Download file from URL

Abstract: implement the Perl package LWP::Simple to download files.

The below subroutine download_file() is used for download file from mirBase.

use LWP::Simple;

#-- fetch file

sub download_file{

my($url, $file_name, $local_dir)=@_;

$url .= '/' unless $url=~/\/$/;

$local_dir .= '/' unless $local_dir=~/\/$/;

#fetch file

my $url_file= $url.$file_name;

my $local_file=$local_dir.$file_name;

my $status = getstore($url_file, $local_file);

#report status

if ( is_success($status) ){

print "downloaded from $url and save it as $local_file\n";

#unzip file

system("gunzip $local_file") if $local_file=~/\.gz$/;

}

else{

print "error downloading file: $status\n";

}

#return

}

#main program

download_file("ftp://mirbase.org/pub/mirbase/CURRENT/", "hairpin.fa.gz", "/home/yuan/Downloads/");

print "ok\n";