where is my text file?

code_wrong · Oct 18, 2005

hi,
I using the following script (from CGI and Perl in easy steps book) as a hit
counter:
it works ... but when I view the files on the host with WSFTP there is no
sign of counter.txt...
the script is in cgi-bin .. which is surely where counter.txt should appear
... but there is no sign of it anywhere .. any ideas?

#!/usr/bin/perl

open(COUNT,"counter.txt");
$num = <COUNT>;
close(COUNT);

$num++;

open(COUNT, ">counter.txt");

print COUNT $num;
close(COUNT);

$num=sprintf("%05d", $num);

print "content-type:text/html\n\n <html>";
print "You are visitor number $num </html>";

code_wrong · Oct 18, 2005

code_wrong said:
hi,
I using the following script (from CGI and Perl in easy steps book) as a
hit counter:
it works ... but when I view the files on the host with WSFTP there is no
sign of counter.txt...
the script is in cgi-bin .. which is surely where counter.txt should
appear .. but there is no sign of it anywhere .. any ideas?

DOH! .. found it ... I couldn't see it for looking at it ;-) it was in my
root directory on the host

Dr.Ruud · Oct 18, 2005

code_wrong:

I using the following script (from CGI and Perl in easy steps book)
as a hit counter:

Try <
Appending a 0-byte per visitor, to a sparse file if available, may be a
better approach.

J. Gleixner · Oct 18, 2005

code_wrong said:
DOH! .. found it ... I couldn't see it for looking at it ;-) it was in my
root directory on the host

Wait a second.. The user-id running your Web server has write privilege
to your root directory? That's not good.

As for a counter, please see:

perldoc -q "I just want to increment the number in the file."

code_wrong · Oct 18, 2005

Purl Gurl said:
code_wrong wrote:

(snipped)

You don't want to do that. If your server is configured
correctly, visitors cannot directly access your cgi-bin
directory. Executables in a cgi-bin directory are
used for server side includes or adjunct programming
for other scripts, located outside your cgi-bin directory.

my cgi-bin directory is located in my home directory along with my
index.shtml file and scripts can be run by inserting a direct url to a
script file ...... This is not good, but it can work as long as say a script
requires certain parametres to run ..for example some form data .. is this
workable?

Your content type is provided by default for html pages
or is printed within a cgi script, as needed.

I don't understand this ..the content type is printed by my script .. but it
does not show up in the source when I view source .. why is this? .. Bear in
mind the script I am using has come from a book ...

this is just another way to invoke the script via SSI

cheeers
cw

Tintin · Oct 19, 2005

code_wrong said:
hi,
I using the following script (from CGI and Perl in easy steps book) as a
hit counter:

Throw that book away. The code example is simply woeful. You will be
learning many, many bad habits if you follow the book.

[horrible code snipped]

code_wrong · Oct 19, 2005

Tintin said:
code_wrong said:

hi,
I using the following script (from CGI and Perl in easy steps book) as a
hit counter:

Click to expand...

Throw that book away. The code example is simply woeful. You will be
learning many, many bad habits if you follow the book.

[horrible code snipped]

how so?

it does go on to demonstrate file locking and permissions ... although ..
since my host is running Windows IIS .... I am not sure if I can set file
permissions

Eric Bohlman · Oct 19, 2005

Tintin said:
Tintin said:

Throw that book away. The code example is simply woeful. You will
be learning many, many bad habits if you follow the book.

[horrible code snipped]

Click to expand...

how so?

it does go on to demonstrate file locking and permissions ... although
.. since my host is running Windows IIS .... I am not sure if I can
set file permissions

#!/usr/bin/perl

No "use warnings" (or -w).
No "use strict".

open(COUNT,"counter.txt");

No check that the open succeeded.
Assumption that the file is in the script's current working directory;
where that is is extremely server-dependent.

$num = <COUNT>;

$num++;

Up to this point, another instance of this script could also have read
the same value from the file.

open(COUNT, ">counter.txt");

No check that the open succeeded.

At this point, the file is empty. If another instance of the script
comes along and tries to read it, its version of $num will be set to
zero.

print COUNT $num;
close(COUNT);

In the first scenario I mentioned, the count will have only gone up by
one even though there were two accesses because both instances started
with the same value. In the second scenario, the count will be reset to
1 because the second instance read from an empty file.

$num=sprintf("%05d", $num);

print "content-type:text/html\n\n <html>";

You've advertised that you're sending out HTML.

print "You are visitor number $num </html>";

But what you've sent out isn't HTML (there's no <title>).

code_wrong · Oct 19, 2005

Eric Bohlman said:
Tintin said:

Throw that book away. The code example is simply woeful. You will
be learning many, many bad habits if you follow the book.

[horrible code snipped]

Click to expand...

how so?

it does go on to demonstrate file locking and permissions ... although
.. since my host is running Windows IIS .... I am not sure if I can
set file permissions

Click to expand...

#!/usr/bin/perl

Click to expand...

No "use warnings" (or -w).
No "use strict".

open(COUNT,"counter.txt");

Click to expand...

No check that the open succeeded.
Assumption that the file is in the script's current working directory;
where that is is extremely server-dependent.

$num = <COUNT>;

$num++;

Click to expand...

Up to this point, another instance of this script could also have read
the same value from the file.

open(COUNT, ">counter.txt");

Click to expand...

No check that the open succeeded.

At this point, the file is empty. If another instance of the script
comes along and tries to read it, its version of $num will be set to
zero.

print COUNT $num;
close(COUNT);

Click to expand...

In the first scenario I mentioned, the count will have only gone up by
one even though there were two accesses because both instances started
with the same value. In the second scenario, the count will be reset to
1 because the second instance read from an empty file.

$num=sprintf("%05d", $num);

Click to expand...

print "content-type:text/html\n\n <html>";

Click to expand...

You've advertised that you're sending out HTML.

print "You are visitor number $num </html>";

Click to expand...

But what you've sent out isn't HTML (there's no <title>).

thanks this is useful stuff ....
I need to add error checking for file open
File locking for reading and writing
I know where the file is because I am choosing the path now:
open(COUNT,"<..\\private\\counter.txt");
and I need to print valid HTML
'use warnings' and 'use strict' I need to look into
cheers

A. Sinan Unur · Oct 19, 2005

I know where the file is because I am choosing the path now:
open(COUNT,"<..\\private\\counter.txt");

Wrong again on at least two counts:

1. The path you specify is still relative. There is no guarantee that
the location to which it is relative will always be the same. You should
specify an absolute path.

2. You still do not check if open succeeded.

3. Using lexical filehandles and the 3-argument form of open is
preferable these days.

So, putting those together:

use strict;
use warnings;

use Readonly;
Readonly my $COUNTER_FILE => 'D:/wwwroot/private/counter.txt';

open my $count_fh, '<', $COUNTER_FILE
or die "Cannot open $COUNTER_FILE: $!";

# etc

'use warnings' and 'use strict' I need to look into

They are not optional, especially at your level. Please read the posting
guidelines.

Sinan

Problem Splitting Text String	2	Dec 29, 2022
MultiThreading	1	Sep 11, 2013
Cgi and file access	8	Jan 16, 2011
Help with my responsive home page	2	Dec 14, 2022
Need help with proper file locking of flatfile data	5	May 25, 2005
FAQ 5.23 I still don't get locking. I just want to increment the number in the file. How can I do th	0	Jan 7, 2011
PHP RSS Feed Aggregator changing to todays date everytime feed is aggregated	1	Jan 11, 2022
Perl if statements evaluates wrongly if we use '=>' as operator	1	Oct 3, 2011

where is my text file?

code_wrong

code_wrong

Dr.Ruud

J. Gleixner

code_wrong

Tintin

code_wrong

Eric Bohlman

code_wrong

A. Sinan Unur

Ask a Question

Similar Threads

Members online

Forum statistics

Latest Threads