Re: Writing variables to Files

This code will get you started. Not tested but I expect it will work. There are three bits - the HTML form, the data processing script and a script which prints to the browser.

If you don't understand what is happening a quick search of the relevant keyword will reward you with a far better explanation than I am likely to be able to tender.

When dealing with files the '>' and '<' chars have special significance. '<' means open for reading. '>' means open for writing AND overwrite the existing file (if any). You will note we use '>>' which means APPEND the data to the end of the file without overwriting the existing data.

Hope this helps

tachyon

HTML FORM

<html>

<head>
    <title>Form</title>
<head>

<body>
    <h1>Mailing list</h1>
    <p>Please fill out this form to subscribe</p>
    <FORM ACTION="/cgi-bin/myscript.cgi" METHOD="post">
    <p>Name: <INPUT TYPE="text" NAME="name"></p>
    <P>Email: <INPUT TYPE="text" NAME="email"></p>
    <p><INPUT TYPE="submit" VALUE="Subscribe me!"</p>
    </FORM>
</body>

</html>
[download]

CGI script. I have assumed it is called myscript.cgi, and lives in the cgi-bin directory when I call it in the form. It needs execute permission - chmod 755

#!/usr/bin/perl -wT
# myscript.cgi

# always use strict
use strict;

# use CGI.pm to process CGI input
use CGI;
my $q = CGI->new;

# use Fcntl to allow file locking
use Fcntl qw(:DEFAULT :flock);

# configuration variables
my $path = '/usr/your/home/logs';
my $name_file = 'names.txt';
my $email_file = 'emails.txt';

# assign form data to variables
my $name = $q->param('name');
my $email = $q->param('email');

# print our data to a file
print_to_file("$path/$name_file", $name);
print_to_file("$path/$email_file", $email);

# print data to file
print_to_file {
    my $file = shift;
    my $data = shift;
    open (FILE, ">>$file") || 
        die "Unable to open $file for appending: $!";
    flock (FILE, LOCK_EX) ||
         die "Can't get an exclusive lock on $file: $!";
    print FILE "$data\n";
    close FILE;
}
[download]

CGI script to output to browser

#!/usr/bin/perl -wT
# myprint.cgi

# always use strict
use strict;

# configuration variables
my $path = '/usr/your/home/logs';
my $name_file = 'names.txt';

# print the header line, and html stuff
print <<HTML;
Content-type: text/html

<html>
<head>
    <title>Names</title>
<head>

<body>
    <h1>Names list</h1>
HTML

# get data from a file into an array and print it
my @file_data = get_file_data("$path/$name_file");
print "<p>Name: $_\n</p>" for @file_data;

# finish neatly
print"</body>\n</html>\n"

# get data from a file
get_file_data {
    my $file = shift;
    open (FILE, "<$file") || 
        die "Unable to read from $file: $!";
    my @data = <FILE>;
    close FILE;
    return @data;
}
[download]

Comment on Re: Writing variables to Files Select or Download Code

Replies are listed 'Best First'.
Re: Re: Writing variables to Files by new_2_perl (Acolyte) on Jun 06, 2001 at 01:31 UTC
Thanks this helps a lot. I'm getting errors still and I found that it's because I don't have the CGI.pm module. I'm using telnet to work on my code in a UNIX shell where the cgi-bin is. Is there a way to get the cgi.pm module and throw it in the UNIX shell bin so I can use it?	[reply]
Re: Re: Re: Writing variables to Files by new_2_perl (Acolyte) on Jun 06, 2001 at 02:06 UTC
ok I go the CGI.pm module working thanks	[reply]