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- Committer: Bazaar Package Importer
- Author(s): Kapil Hari Paranjape
- Date: 2007-05-09 07:33:04 UTC
- mfrom: (1.1.2 upstream)
- Revision ID: james.westby@ubuntu.com-20070509073304-ywptg9g6iiitsg17
Tags: 3.2.1-1
* New upstream version (3.2.1). Closes: #421451.
- can fetch and execute a local javascript file
if required by local html file.
- provide COPYING and CHANGES files.
* debian/rules:
- add CHANGES to dh_installchangelogs line.
- add dh_installman entry to install the man page.
* debian/copyright: updated to include the COPYING file.
* debian/edbrowse.1: added a basic man page.
- can fetch and execute a local javascript file
if required by local html file.
- provide COPYING and CHANGES files.
* debian/rules:
- add CHANGES to dh_installchangelogs line.
- add dh_installman entry to install the man page.
* debian/copyright: updated to include the COPYING file.
* debian/edbrowse.1: added a basic man page.
added
removed
edbdoc.html
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<LI><A HREF=#cook> Cookies </A>
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<LI><A HREF=#ssl> Secure Connections </A>
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<LI><A HREF=#ftp> FTP Retrievals </A>
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<LI><A HREF=#proxy> Proxy Servers </A>
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<LI><A HREF=#frame> Frames </A>
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</UL>
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<LI><A HREF=#filter> Mail Filtering </A>
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</UL>
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<H4> Chapter 8, Database Access </H4>
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<UL>
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<LI><A HREF=#sqlb> Building edbrowse with Database Access </A>
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<LI><A HREF=#rtb> Reading Tables </A>
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<LI><A HREF=#insupd> Insert, Update, Delete </A>
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<LI><A HREF=#td> Table Descriptors </A>
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</UL>
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<H3 align=center> <A NAME=auth> Author </A> </H3>
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<P><PRE><font size=3 face=Arial,Helvetica,sans-serif>Karl Dahlke
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<A HREF=mailto:karl@eklhad.net>karl@eklhad.net</A>
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<A HREF=mailto:eklhad@comcast.net>eklhad@comcast.net</A>
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248-524-1004 (during regular business hours)
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</font></PRE>
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<H3 align=center> <A NAME=copy> Copyright Notice </A> </H3>
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This program is copyright (C) (C) Karl Dahlke, 2000-2006.
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This program is copyright (C) (C) Karl Dahlke, 2000-2007.
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It is made available by the author under the terms of the GNU General Public License (GPL),
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as articulated by the Free Software Foundation.
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It may be used for any purpose, and redistributed, provided this copyright notice is included.
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et: edit this web page as pure text
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vs: verify ssl connections (toggle)
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ip: show referenced ip numbers, usually for saved mail messages
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sc: show columns
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sm: send mail [account number]
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</font></PRE>
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Since these edits have implications outside the scope of this program,
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there is no undo capability.
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When you make a change it is made.
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With this in mind, I borrowed a good idea from Microsoft.
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(That's one.)
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With this in mind, I borrowed a good idea from Microsoft, which, as you might expect, originated with Apple.
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The deleted file isn't actually deleted;
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it is moved to your recycle bin,
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located in $HOME/.recycle.
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trying to steal your account numbers and passwords.
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You can grab a certificate file <A HREF=ssl-certs>here</A>,
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but I don't always keep it up to date.
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If you don't have this file,
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On some Linux distributions, you can run `cd /etc/ssl/certs ; cat * >../edbrowse-certs'
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to capture ssl certificates that are as current as your linux system.
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If you don't have or create this file,
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or, if you don't specify its location in your config file,
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you will not be able to verify secure connections, and you will be warned accordingly.
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Some browsers don't have this feature at all, so it's not the end of the world,
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I use other, expendable passwords when the connection is not secure.
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<P>
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Please don't fall for all those email scams
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Please don't fall for all those "phishing" email scams
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that tell you your login has expired, and would you please log in again using this convenient form.
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The mail is forged to look legitimate,
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and the form actually sends your secret password to a thief,
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so you just have to wait until it's done.
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(Depending on your operating system, you could switch to another virtual console/window and check on the length of the local file.)
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<H3 align=center> <A NAME=proxy> Proxy Servers </A> </H3>
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A proxy server is a web server that sits between your web browser and remote websites.
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It intercepts your requests for web pages and forwards them to the system that hosts
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the site you are browsing.
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Proxy servers are used for a variety of reasons.
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Here are just a few of them:
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<OL>
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<P><LI>Efficiency.
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The proxy server may be able to store previously-accessed webpages
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(known as caching).
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If your connection to the proxy is faster than your connection to the rest of the network,
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then caching insures that frequently-accessed web pages load quickly.
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<P><LI>Policies.
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Some firewall administrators require their users to use
2328
a proxy server.
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<P><LI>Anonymity.
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There are so-called anonymizing
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proxy servers that hide your IP address from the websites that you browse.
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</OL>
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<P>
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If you wish to use a proxy server for http traffic, simply set the proxy
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option in your configuration file.
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Provide the hostname and port, separated by a colon.
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For example:
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<P>
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proxy = proxy.campus.edu:3128
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<p>
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Note that proxies often listen on ports other than port 80.
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Squid is a proxy server that comes bundled with some Linux distributions, and it uses
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port 3128 by default.
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<p>
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Presently, edbrowse only handles proxying of standard http.
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Secure http and ftp
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can both be proxied, but this functionality is not implemented.
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<H3 align=center> <A NAME=frame> Frames </A> </H3>
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Frames are a mechanism whereby a web page can fetch and display several other web pages on the screen at once.
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I set this when looking at other people's mail, such as my wife's account.
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I don't want her mail sent somewhere else because it matches one of my filter rules.
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<H3 align=center> <A NAME=sqlb> Building edbrowse with Database Access </A> </H3>
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If you simply type make, you get edbrowse, with no database interface.
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Two other targets support database access.
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Run either `make edbrowseodbc' or make `edbrowseinf'.
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The former uses odbc to access just about any sql database,
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and the latter uses the
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<A HREF=http://www.informix.com>Informix</A> interface.
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If you would like to test the odbc interface,
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or write a new interface, e.g. for Oracle or mysql,
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I will be eternally grateful.
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You are basically implementing the interface described in dbapi.h,
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using the C database development toolkit provided by the vendor.
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The easiest way to proceed is to copy one of the two files that is already there,
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dbinfx.ec or dbodbc.c, and make changes as necessary.
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<H3 align=center> <A NAME=rtb> Reading Tables </A> </H3>
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When a file name is of a certain format, with the http:// in front etc,
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it is deemed to be a url.
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Edbrowse does not look on your computer for the file; it goes out to the internet.
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Similarly, when the file name has a certain format,
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it is assumed to be a table or view in the database.
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If you have a table called customers, you follow it up with a right bracket.
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<P>
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e customers]
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<P>
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This allows you to bring in the entire table,
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or portions thereof, one row per line, with fields delimited by pipes.
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If the result looks like a bunch of numbers and pipes,
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and you have forgottten the structure of the table,
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use the sc (show columns) command.
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The output might look like this.
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<P><PRE><font size=3 face=Arial,Helvetica,sans-serif>Table customers, 536281 rows
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1 *custnum int
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2 firstname string
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3 lastname string
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4 birthdate date
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5 sex char
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6 email string
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7 picture blob
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</font></PRE>
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<P>
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The first column is a unique number that designates this particular customer.
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After all, two customers could have the same first and last name,
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and even the same birthdate.
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Serial numbers are <em>always</em> a good idea,
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and that usually becomes the primary key.
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This is indicated by a star, just before the column name.
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If edbrowse changes or deletes a record, the primary key is used.
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I assume, at all times, that the key determines a unique record in the database,
3579
and that each record appears at most once in an editing session.
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<P>
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Note that edbrowse can support a primary key with two columns, such as a serial number and a modifier.
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I actually have some tables at work that look like this.
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<P>
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The table syntax is more than just an identifier and a right bracket.
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You can follow the right bracket with a where clause.
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This is important if you don't want the entire table,
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especially if there are millions of rows.
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Here are some table commands and their meanings.
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<P>
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customers]
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<br>
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Set the buffer up for the customers table, but don't fetch any rows.
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<P>
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customers]*
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<br>
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Fetch all the rows in the table.
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<P>
3603
customers]37
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<br>
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Fetch the customer whose serial number is 37.
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The primary key is assumed; your table has to have a primary key
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if you are going to use this syntax.
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<P>
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customers]1=37
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<br>
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Fetch the row whose first column is 37.
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<P>
3615
customers]37-59
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<br>
3617
Fetch the customers with serial numbers between 37 and 59 inclusive.
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<P>
3620
customers]3=Smith
3621
<br>
3622
Fetch the customers whose last name is Smith.
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<P>
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customers]lastname=Smith
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<br>
3627
Same as above.
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<P>
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customers]last=Smith
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<br>
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Same as above.
3633
If the string uniquely gloms onto a column name, we're all set.
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<P>
3636
customers]last=Barn*
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<br>
3638
Fetch the customers whose last names begin with Barn.
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<P>
3641
customers]birth=01/01/1960-12/31/1960
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<br>
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Fetch the customers who were born in 1960.
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<P>
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It is sometimes best to edit with a blank template, i.e. without a where clause.
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Then, you can read in whatever rows you like.
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Type an r before any of the strings shown above to read rows into your buffer.
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Note, you cannot read data from different tables into the same buffer,
3650
but you can switch to another editing session to look at another table,
3651
without losing the rows you are working on.
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<P>
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When reading rows into a growing buffer, you can usually omit the table, since it has to be customers] every time.
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For instance, you can bring in customer #738 by typing `r customers]738' or `r 738'.
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<P>
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If you want a clean slate, type `rf' to refresh the buffer.
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This brings you back to a template for the table, with no rows.
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WARNING - do not clear your buffer by deleting all the rows,
3661
as that will delete the corresponding entries in the database.
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This feature works just like directory mode -
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your edits are translated into actions in the real world, so be careful.
3664
Referential integrity will usually save you from this accidental delete disaster,
3665
if you routinely use this sql feature to link tables together,
3666
which is a good idea at many levels.
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<P>
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Now, how about the seventh column in our example, the one called "picture"?
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This is the customer's picture, a jpg image that is in binary,
3671
and cannot be easily folded into an editing session.
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Instead, it is stored in another buffer,
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e.g. buffer 9, and this is indicated by <9>.
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You can switch to session 9 and save the file, or throw it away.
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<P>
3677
2139|Fred|Flintstone|08/21/1969|M|foo@bar.bar.com|<9>
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<P>
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To do anything with the database, your config file must specify
3681
the name of the database, the login, and the password.
3682
(The last two can sometimes be omitted, if they are inferred from your identity on the computer.)
3683
Here is how the line might look
3684
if you are tapping into the retail database, where the customers table resides.
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<P>
3687
database = retail,mylogin,mypassword
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<P>
3690
Although this cannot be changed on the fly, you can access other databases by vectoring through this one.
3691
For instance, you can read the parts table in the inventory database by calling up inventory:parts].
3692
This is standard sql syntax for looking at tables in another database;
3693
I just pass it through.
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<H3 align=center> <A NAME=insupd> Insert, Update, Delete </A> </H3>
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Adding database rows is substantially different from adding text.
3698
Since a row may contain a dozen fields, and you may not remember what goes where,
3699
edbrowse prompts you for each field in turn.
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It also checks the integrity of each field as you go,
3701
e.g. a date has to look like mm/dd/yyyy etc.
3702
If a row cannot be added because of a database error,
3703
edbrowse prints the error,
3704
and data entry continues;
3705
giving you a chance to reenter the row.
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Data entry stops when you enter a period all by itself,
3707
no matter what field you are on.
3708
The rows that were entered successfully will be present in your buffer,
3709
and the current line is the last entered row.
3710
Note that blobs cannot be entered at this time.
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<P>
3713
Use the substitute command to update a row.
3714
Make sure you don't accidentally introduce an additional pipe, or remove a pipe.
3715
Key columns cannot be modified.
3716
If you are updating many rows with one command,
3717
through a range or through g//s,
3718
and an error occurs while updating the database,
3719
substitution stops in its tracks.
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The editing session will reflect the database,
3721
with some rows changed and others untouched.
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There are many reasons for these update errors, including datatype mismatch
3723
(e.g. pushing an integer into a date field), and check constraints
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(e.g. putting J in for sex, instead of M or F).
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If you have any say in the database design,
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apply check constraints wherever they make sense.
3727
They will protect you from erroneous substitutions, wich would produce inconsistent updates.
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<P>
3730
Delete works as you would expect; delete a row,
3731
and the corresponding entry disappears.
3732
There is no undo command.
3733
It couldn't be done in any case, since you may have selected only part of the row (see below),
3734
and I wouldn't have all the data to put the row back.
3735
As mentioned before, referential integrity should be employed wherever it makes sense.
3736
As a last check, I only let you delete 100 rows at a time.
3737
Be careful, and run regular backups.
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<H3 align=center> <A NAME=td> Table Descriptors </A> </H3>
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Suppose a table contains 100 fields.
3742
Displaying all those fields is awkward, to say the least.
3743
Sometimes you are interested in a group of 6 fields,
3744
and sometimes you are interested in another group of 8.
3745
You can set up virtual tables, similar to views, in your config file.
3746
The short name is the alias, and you can call up the table using this alias.
3747
It will contain only the columns you specify.
3748
Here are two descriptors for the aforementioned customers table.
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3750
<P><PRE><font size=3 face=Arial,Helvetica,sans-serif>table {
3751
tname = customers
3752
# cnm is my cryptic shorthand for customer name
3753
# I want to be cryptic here, cause I'm going to be typing this a lot.
3754
tshort = cnm
3755
cols = custnum,firstname,lastname
3756
# Specify the primary key, in this case, the first column selected.
3757
keycol = 1
3758
}
3759
3760
table {
3761
tname = customers
3762
# All I care about here is customer and birthdate.
3763
tshort = cbd
3764
cols = birthdate,custnum
3765
keycol = 2
3766
}
3767
</font></PRE>
3768
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<P>
3770
When inserting a row through one of these descriptors,
3771
remember that you are only specifying a subset of the columns in the table.
3772
The other columns will be null, or they will take on their default values,
3773
as specified by the schema.
3774
If you receive a Not-Null error, it could be due to one of the other columns,
3775
which requires an entered value.
3776
It is usually safer to insert a row using the complete table.
3777
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<H3 align=center> <A NAME=end> Wrap up </A> </H3>
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3779
3474
3780
That concludes the user's guide.
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As you can see, edbrowse is a difficult program to master, but an easy program to use.
3476
3782
I believe this is the key to success for any blind user or programmer.
3477
3783
One can certainly paste a screen reader on top of an existing 2 dimensional program
3478
such as emacs or lynx, and get "up and running" quickly,
3784
such as emacs or lynx, and get up and running quickly,
3479
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but to be truly competitive in the workplace, or efficient at home,
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you need a <A HREF=http://www.eklhad.net/cli.html>command line interface</a>.
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Edbrowse is an important step in this direction.
Loggerhead is a web-based interface for Breezy
Version: 2.0.1