ch50.htm

linux-unix130.linux.and.unix.ebooks130 linux and unix ebookslinuxLearning Linux - Collection of 12 E

<P>The <TT>Name</TT> entry can have spaces or other special symbols in it, because

it is echoed as a complete string. The <TT>Numb</TT> entry is for the location of

the entry on your Gopher menu. For example, suppose you had the preceding entry and

two other files, shown by using <TT>cat</TT> to display their contents:</P>

<PRE><FONT COLOR="#0066FF">$ cat q1.sales

Name=Company Sales for the First Quarter, 1997

Numb=1



$ cat q2.sales

Name=Company Sales for the Second Quarter, 1997

Numb=2



$cat q3.sales

Name=Company Sales for the Third Quarter, 1997

</FONT></PRE>



<PRE><FONT COLOR="#0066FF">Numb=3

</FONT></PRE>

<P>When these entries are displayed in a Gopher menu they will look like this:<FONT

COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">1. Company Sales for the First Quarter, 1997

2. Company Sales for the Second Quarter, 1997

3. Company Sales for the Third Quarter, 1997

</FONT></PRE>

<P>The order of filenames in the <TT>.cap</TT> directory doesn't matter, but you

shouldn't have the same <TT>Numb</TT> entry more than once.</P>

<P>An alternative to using the <TT>.cap</TT> directory approach (which allows for

easy addition of new files) is to use a single master file for each document you

are making available. This file goes in your Gopher top directory and is called <TT>.names</TT>.

Here's the <TT>.names</TT> file for the same three files just mentioned:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">$ cd /usr/gopher/data

$ cat .names

# My Gopher main .names file



Path=./q1.sales

Name=Company Sales for the First Quarter, 1997

Numb=1



Path=./q2.sales

Name=Company Sales for the Second Quarter, 1997

Numb=2



Path=./q3.sales

Name=Company Sales for the Third Quarter, 1997



Numb=3

</FONT></PRE>

<P>As you can see, this format contains the same information but adds the filename

(which was not needed in <TT>.cap</TT> since the filenames were the same). One advantage

to using a <TT>.names</TT> file is that you can reorder your menu entries much more

easily because you only have one file to work with instead of several. Also, the

<TT>.names</TT> file enables you to add an abstract describing the file. For example,

you could have the following entry in a <TT>.names</TT> file:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">Path=./gopher

Name=How to Set up A Gopher Service

Numb=16

Abstract=This document shows the steps you need to take to 

</FONT></PRE>



<PRE><FONT COLOR="#0066FF">set up a Gopher service.

</FONT></PRE>

<P>You can get a little fancier with Gopher and have a menu item lead to another

menu, or to another machine entirely. This is done with links, controlled by a link

file, which ends with <TT>.link</TT>. A <TT>.link</TT> file has five pieces of information

in it, in the same format as this example:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">Name=More Sales Info

Type=1

Port=70

Path=/usr/gopher/data/more_sales

</FONT></PRE>



<PRE><FONT COLOR="#0066FF">Host=wizard.tpci.com

</FONT></PRE>

<P>The <TT>Name</TT> entry is what a user sees on the Gopher menu, and can be any

type of description you want, regardless of what else is in the link file. The <TT>Type</TT>

field has a number showing the type of document the file links to. The following

are all valid numbers: 

<PRE><FONT COLOR="#0066FF"><TT>0</TT> Text</FONT></PRE>



<PRE><FONT COLOR="#0066FF"><TT>1</TT> Directory</FONT></PRE>



<PRE><FONT COLOR="#0066FF">2 CSO name server</FONT></PRE>



<PRE><FONT COLOR="#0066FF"><TT>7</TT> Full text index</FONT></PRE>



<PRE><FONT COLOR="#0066FF"><TT>8</TT> telnet session</FONT></PRE>



<PRE><FONT COLOR="#0066FF"><TT>9</TT> Binary</FONT></PRE>



<PRE><FONT COLOR="#0066FF"><TT>h</TT> HTML file</FONT></PRE>



<PRE><FONT COLOR="#0066FF"><TT>I</TT> Image file</FONT></PRE>



<PRE><FONT COLOR="#0066FF"><TT>M</TT> MIME file



<TT>s</TT> Sound file</FONT></PRE>

<P>These types are the same as the list shown earlier in this chapter for the types

of files Gopher supports, although it's a little shorter here.</P>



<P>The <TT>Port</TT> field is the port for a connection to a remote system (if that's

where the link leads), and the <TT>Path</TT> field is where the file is on the local

or remote server. The <TT>Host</TT> field, not surprisingly, is the name of the host

the file resides on. If you are setting up a link to another machine via FTP or WAIS,

you need to specify the path to include the service name and any arguments. For example,

if your Gopher menu leads users to a file on another machine through FTP, your link

file may look like this:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">Name=More Sales Info

Type=1

Port=+

Path=ftp:chatton.bigcat.com@/usr/gopher/cats

Host=+

</FONT></PRE>

<P>The plus signs used in the <TT>Port</TT> and <TT>Host</TT> fields instruct the

FTP service on the remote machine to return results to this machine using default

ports (such as TCP port 21 for FTP). For a link to a WAIS directory, this would be

the format:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">Name=More Sales Info

Type=7

Port=+

Path=waisrc:/usr/wais/data

Host=+

</FONT></PRE>

<P>Finally, you may want to have a menu item execute a program. You can do this by

having the <TT>Path</TT> field use the <TT>exec</TT> command:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">Path=exec: &quot;args&quot; : do_this

</FONT></PRE>

<P>In this command, do_this is the program you want to execute and args are any arguments

to be passed to do_this. If you have no arguments to pass, leave the quotation marks

empty. This format is a little awkward, but it does work.

<H3 ALIGN="CENTER"><A NAME="Heading11<FONT COLOR="#000077">Starting Gopher</FONT></H3>

<P>A Gopher server can be started either from the <TT>rc</TT> startup files, from

the command line, or from the <TT>inetd</TT> daemon. From the command line or the

<TT>rc</TT> files, you need a command line similar to this:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">/usr/local/etc/gopherd /usr/gopher/gopher-data 70

</FONT></PRE>

<P>which starts the daemon with the directory the startup Gopher menus reside in

and the port number for connections.</P>

<P>The <TT>gopherd</TT> command line accepts a number of optional flags to control

its behavior, although most mirror entries in the configuration files. Valid flags

are listed here: <TT>-C</TT> Disables directory caching</P>

<P><TT>-c</TT> Runs without <TT>chroot</TT> restrictions</P>

<P><TT>-D</TT> Enables debugging</P>

<P><TT>-I</TT> <TT>inetd</TT> is used to invoke <TT>gopherd</TT></P>

<P><TT>-L</TT> Followed by a value for the maximum load average</P>

<P><TT>-l</TT> Log file to record connections (filename follows the option)</P>

<P><TT>-o</TT> Specifies an alternate configuration file from <TT>gopherd.conf</TT>

(filename follows the option)<BR>

<BR>

<TT>-u</TT> Sets the name of the owner running <TT>gopherd</TT> (valid username must

follow the option)<BR>

<BR>

To help secure your system, use <TT>chroot</TT> to create a separate file system

structure for the gopher area (as you did with FTP: see Chapter 48, &quot;FTP and

Anonymous FTP Sites&quot;). The <TT>-c</TT> option is not as secure as running <TT>gopherd</TT>

with <TT>chroot</TT> active. Also, the <TT>-u</TT> option should be used to make

<TT>gopherd</TT> run as a standard user's process, instead of as root. This helps

protect against holes in the daemon that a hacker could exploit.</P>



<P>If you want to run Gopher under <TT>inetd</TT> (started whenever a request for

the service arrives), modify the <TT>/etc/services</TT> and <TT>/etc/inetd.conf</TT>

file to include a line for Gopher. Normally, the entry in <TT>/etc/services</TT>

looks like this:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">gopher     70/tcp     

</FONT></PRE>

<P>And the entry in <TT>/etc/inetd.conf</TT> looks like<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">gopher     stream     tcp     nowait     root 



    /usr/local/etc/gopherd gopherd -I -u username

</FONT></PRE>

<P>where username is the name of the user to run <TT>gopherd</TT> as (you can set

up a specific account for <TT>gopher</TT> in /<TT>etc/passwd</TT> with standard permissions).</P>

<P>Once the Gopher server process is up and running, you can test your Gopher installation.

You will need a Gopher client. Use the Gopher client to connect to your Gopher server

(using your host name), and you should see the top directory of your Gopher resources.

Another way to test your Gopher system is to use telnet. Use Telnet to connect to

the Gopher port, using a command like this:</P>

<PRE><FONT COLOR="#0066FF">telnet gopher 70

</FONT></PRE>

<P>If the connection is properly made, you will see your Gopher system on the screen.</P>

<P>Yet another alternative to test your system is to use the program <TT>gopherls</TT>,

which requires the name of the directory your Gopher source resides in. To start

<TT>gopherls</TT>, you would issue the command</P>

<PRE><FONT COLOR="#0066FF">gopherls /usr/wais/gopher/data

</FONT></PRE>

<P>specifying your Gopher data directory. You can use this technique to test new

Gopher directories as you develop them.

<H3 ALIGN="CENTER"><A NAME="Heading12<FONT COLOR="#000077">Letting the World

Know</FONT></H3>

<P>Because you have spent a lot of time setting up your Gopher service, you can now

let everyone else on the Internet know about it. (Of course, you should only do this

when your Gopher service is ready, and if you want to allow general access. Don't

follow these steps if you are granting access only to a few people or your local

area network.)</P>

<P>To have your Gopher service listed in the main Gopher service directories, send

an e-mail message to the following address:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">[e-mail]

</FONT></PRE>

<P>Include the Gopher service's full name as it appears on your main menu, your host's

name and IP address, the port number Gopher uses (which should be TCP port 70 for

general Internet access), the e-mail account of the Gopher administrator, and a short

paragraph describing your service. If you want, you can also provide a string that

gives the path to the data directory, although since most Gopher systems start in

the root directory, this string isn't necessary unless you have sub-menus for different

purposes.

<H3 ALIGN="CENTER"><A NAME="Heading13<FONT COLOR="#000077">Summary</FONT></H3>

<P>After all that, your Gopher service should be ready to use. You do need to set

up the Gopher file entries, but that is beyond the scope of this chapter. Consult

a good Internet or Gopher book for more information on Gopher directories, files,

and entries. Gopher is a handy utility if you have volumes of information you want

to share. Although the configuration process can take a while, once it's completed,

the Gopher system tends to work very well.









</td>
</tr>
</table>
<!-- begin footer information -->


</body></html>