How do I read a file on my webserver from my Perl CGI script and then print the data?

Question

I have a file "a.cpm" on my webserver. I have a handler that when you go to asdasd.com/a.cpm it starts the CGI perl script. I have tried reading the file then printing the data but it doesnt do anything.

#!/usr/bin/perl
print "Content-type:text/html\r\n\r\n";
print "test string";
print "<br>";
$filepath = $ENV{'PATH_TRANSLATED'};
open FILE, $filepath or die $!;
my @lines = <FILE>;
while (my $line = <FILE>) 
{
print $_;
}

Have you checked your webserver's error log? Have you tried a Hello World CGI script (without the file access)? — cjm, Nov 28 '10 at 08:48

score 2 · Answer 1 · edited May 23 '17 at 12:04

2

Have you read brian d foy's How can I troubleshoot my Perl CGI script? and followed through with its suggestions?

edited May 23 '17 at 12:04

Community

1
1

answered Nov 28 '10 at 08:51

cjm

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For the next time: http://stackoverflow.com/questions/2165022/how-can-i-troubleshoot-my-perl-cgi-script – daxim Nov 28 '10 at 13:47
@daxim, thanks. I thought he'd moved that to SO, but I couldn't find it. – cjm Nov 28 '10 at 17:18

score 0 · Answer 2 · answered Apr 27 '14 at 22:06

The accepted answer does not work out of the box -- here is a slight variation that does -- just adjust the path to file.txt:

#!/usr/bin/perl
use CGI qw(:standard);
print <<HTML;
Content-type: text/html

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head><title>Path Translated</title></head>
<body>
HTML

open FILE, "file.txt" or die "could not open filename";
while(<FILE>) {
    print $_;
}
close FILE;

print <<HTML;   
</body>
</html>
HTML

Philar · Accepted Answer · 2010-11-28T10:56:44.647

If your handler is working fine and you have changed the file permissions chmod a+x of your CGI script, then I suggest using the CGI module as shown in the code below.

#!/usr/bin/perl
use CGI qw(:standard);
print <<HTML;
Content-type: text/html

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head><title>Path Translated</title></head>
<body>
HTML

$filepath = $ENV{'PATH_TRANSLATED'};
open FILE, $filepath or die $!;
my @lines = <FILE>;
while (my $line = <FILE>) 
{
    print $_;
 }

print <<HTML;   
</body>
</html>
HTML

EDIT: Taint checking, turning on the warnings and using strict are good practice, more so for web applications.

#!/usr/bin/perl -wT
use strict;

If you turn on taint checking, you're going to have to untaint `$ENV{'PATH_TRANSLATED'}` before you can use it to open a file. — cjm, Nov 28 '10 at 17:20

How do I read a file on my webserver from my Perl CGI script and then print the data?

3 Answers3