perl file upload can't init filehandle
Question
I tried to use this very simple script for uploading a file to my server. For some reason it is not working. I get the following message in my apache error log:
Use of uninitialized value in <HANDLE> at /opt/www/demo1/upload/image_upload_2.pl line 15.
readline() on unopened filehandle at /opt/www/demo1/upload/image_upload_2.pl line 15.
#!/usr/bin/perl -w
use CGI;
$upload_dir = "/opt/www/demo1/upload/data";
$query = new CGI;
$filename = $query->param("photo");
$filename =~ s/.*[\/\\](.*)/$1/;
$upload_filehandle = $query->upload("photo");
open UPLOADFILE, ">$upload_dir/$filename";
binmode UPLOADFILE;
while ( <$upload_filehandle> )
{
print UPLOADFILE;
}
close UPLOADFILE;
1
Any ideas what is wrong there? Thanks mx
2 answers
solution1
7 ACCPTED 2010-07-07 16:33:39
File upload forms need to specify enctype="multipart/form-data" . See W3C documentation .
In addition, note the following:
#!/usr/bin/perl
use strict; use warnings;
use CGI;
my $upload_dir = "/opt/www/demo1/upload/data";
my $query = CGI->new; # avoid indirect object notation
my $filename = $query->param("photo");
$filename =~ s/.*[\/\\](.*)/$1/; # this validation looks suspect
my $target = "$upload_dir/$filename";
# since you are reading binary data, use read to
# read chunks of a specific size
my $upload_filehandle = $query->upload("photo");
if ( defined $upload_filehandle ) {
my $io_handle = $upload_filehandle->handle;
# use lexical filehandles, 3-arg form of open
# check for errors after open
open my $uploadfile, '>', $target
or die "Cannot open '$target': $!";
binmode $uploadfile;
my $buffer;
while (my $bytesread = $io_handle->read($buffer,1024)) {
print $uploadfile $buffer
or die "Error writing to '$target': $!";
}
close $uploadfile
or die "Error closing '$target': $!";
}
See CGI documentation .
solution2
0 2014-01-30 12:21:00
If you are uploading a text file then below should be set in <head> of html file:
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
Otherwise the $file_name = $query->param("file_name") is defined in scalar context ( print $file_name ) and undef in file context ( <$file_name> ).
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