Changing error messages

Albert Lunde Albert-Lunde at nwu.edu
Mon Dec 4 10:59:13 EST 1995


> are these messages "wired in?"  As in, if I wanted these messages replaced
> with other messages--maybe something novices could understand--what would I
> need to do?  Edit status messages built into the server software?  Based on
> my vague memories of running Webstar, I'm guessing that these messages
> occur at the server level, but is this so, and if so, are they coming from
> "my" server?  If I can't access <http://www.foo.com/>, from whence comes
> that message?  A local file?  Other considerations?

Generally, for a number of protocols that use 3 digit error codes,
plus messages: FTP, SMP,  NNTP, and HTTP, all that really matters to
the protocol is the numbers. The first digit indicates the severity
of errors, and the common normal and error responses are standardized.

So you _can_ change the message text by hacking the server source
or binary, but a well-designed client will provide its own
interpretation of common conditions, and only pass thru the server
error text for totally unexpected errors.

Admittedly this suggests that a number of clients are not "well
designed" (or that they fall back on the server error text when
a numeric code is overloaded for too many purposes).

(I think some of the cryptic nature of WWW error messages, derives
from code like libwww in client software, that tries to present a common
interface to a number of protocols. This often has the effect of
hiding details, specific to one protcol. On the other hand, a lot
of this detail is almost meaningless to the end user.

It is hard in gopher, and to some extent in http, to distingush between
server error and network trouble, when for example, the remote system
is slow in responding. So some error treatment is forced to be generic.)

So it may be useful to change error messages for some exceptional
conditions, but you shouldn't rely on users seeing it in all cases.

Test the changes with some actual client software.

--
    Albert Lunde                      Albert-Lunde at nwu.edu

---
    Albert Lunde                      Albert-Lunde at nwu.edu




More information about the Web4lib mailing list