Re: Validator is not working even now

On Jun 24, 2005, at 14:35, rahul gupta wrote:
>  I did try that you have written but result is exactly
> same as earlier.

If the validator still does not work now that you have (apparently) 
reinstalled openSP, I can see two possible causes:
- a problem with your sgml-lib (but the validator used to work, right?)
- openSP is not working as it should

One question: when you re-installed onsgmls, did you compile it 
yourself or install it from a package? If you compiled it yourself, did 
you use the --enable-http compile option?

> Can you explain me DOCTYPE tag in some detail.
>  Please tell me how validator works and parse the HTML through a DTD.

You realise this is a very vast topic, don't you? There is a lot of 
documentation on the Web about SGML, DTDs, XML, validation, I frankly 
suggest you do some research by yourself.

*very* basically,

- markup languages are defined in technical specifications
- these specifications usually provide a machine-readable formal 
grammar for the language (in our case, a DTD)
- documents declare which document type their are using. That's the 
infamous "DOCTYPE declaration", which uses a well-known identifier 
(FPI) and/or URI (SI) to refer to the DTD they claim to be using
- parsers use this declaration to know what grammar the document uses
- validators, in particular, are parsers that compare the document 
against the formal grammar (the DTD). In order to do so, they either 
have the DTD in a local catalog (which is the case for the validator, 
it has a catalog of the most common languages) or fetch it over the 



Received on Friday, 24 June 2005 06:20:15 UTC