This is the mail archive of the systemtap@sourceware.org mailing list for the systemtap project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[Bug tapsets/2861] user_string fault handling


------- Additional Comments From jamesd dot wi at gmail dot com  2006-06-29 03:16 -------
Subject: Re:  user_string fault handling

On 29 Jun 2006 01:08:46 -0000, fche at redhat dot com
<sourceware-bugzilla@sourceware.org> wrote:
>
> ------- Additional Comments From fche at redhat dot com  2006-06-29 01:08 -------
> > Is there really a need for a caller-specified error message that would
> > justify the overhead of the extra strcpy?
>
> Yes, as a style matter, in order to avoid setting arbitrary english strings as
> values that may need to be further processed by script.
>
> > I'd like to avoid changing all the current code.  How about
> >
> > user_string(addr) ==> returns "<unknown>" on error

shouldn't it return NULL or possibly -1 and then the script then
request the exact error code as common with C programming?

James Dickens
uadmin.blogspot.com



>
> This works okay only if the returned string is simply going to be passed
> straight to an english-speaking user, and not e.g. tested by the script
> for its own error-detection purposes.  Plus it has no way of telling apart
> legal occurrences of the fixed string "<unknown>" from the error indication.
> In the absence of multiple return values and exceptions, letting the caller
> specify their favorite soft-error value seems to be he next best thing.
>
> > user_string(addr, 0) ==> same as above but prints warning
>
> The ", 0" setting is not helpful (nor is the "0" too informative).  We
> don't print run-time warnings at the present, and for good reason: they
> are only noise.
>
> > user_string(addr, 1) ==> prints error message and sets lasterr
>
> I don't find the ", 1" is too informative.
>
>
> Nevertheless, I am not strongly attached to these options, so if others
> wish to voice support for hunt's suggestion, or offer new ones, please do.
>
>
> --
>
>
> http://sourceware.org/bugzilla/show_bug.cgi?id=2861
>
> ------- You are receiving this mail because: -------
> You are the assignee for the bug, or are watching the assignee.
>


-- 


http://sourceware.org/bugzilla/show_bug.cgi?id=2861

------- You are receiving this mail because: -------
You are the assignee for the bug, or are watching the assignee.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]