Side-by-side configuration is incorrect reported as permission denied

Andrew DeFaria
Mon Aug 13 15:01:00 GMT 2012

On 08/13/2012 07:42 AM, Corinna Vinschen wrote:
>>> There's a difference between cmd and Cygwin.  Cmd is a shell, Cygwin is
>>> just the underlying shared lib providing a generic API.
>> OK so bash...
> Ok so bash what?
You were saying cmd is a shell and Cygwin is a shared lib. So then 
perhaps the responsibility should fall to bash - a shell...
>>> If an error occurs, it's the shell's responsibility to print an error
>>> message in the first place.  All messages printed by Cygwin are not
>>> controllable by the calling application.  Therefore we usually only
>>> print messages from the DLL if something very serious happens from the
>>> DLLs perspective.  Some arbitrary Windows error code returned from
>>> CreateProcess is usually not something actually serious.  There was
>>> just "some" reason that an application couldn't be started.
>> IMHO "some" reason that the user should be alerted about. How is it
>> helpful to the end user to suppress the error message?
> Huh?  Somehow you swapping cause and effect.  There is no "suppressed"
> error message.  Generating an error message is the task of the shell in
> the first place.
There was an error message that cmd showed that bash did not. To me 
that's suppression.
> It's not that the OS generates an error message and cmd lets it slip
> through while Cygwin (or bash) "suppress" it.  It's the CreateProcess
> call which generates an error code ERROR_SXS_CANT_GEN_ACTCTX and cmd
> printing the connected error message, just like bash gets an error code
> EACCES and prints the connected error message "Permission denied".
Plumbing and mechanics aside, I'm just saying the user should be told 
the underlying problem. If ERROR_SXS_CANT_GEN_ACTCTX is the error code 
could ya at least print that as a string? It would give the user a 
fighting change and finding a solution...
>>> Also, where do you draw the border?  Which windows error code is serious
>>> enough to justify a (pretty intrusive!) error message from the underlying
>>> library and which isn't?
>> I would draw the border at "if there's an error message".
> Again, cause and effect turned upside down.
Not really. You seem stuck in thinking in only error codes - I'm 
thinking in solutions, regardless of the mechanics to get there. IOW the 
goal is to inform the user not only that an error occurred but what that 
errors was so that the user can fix it. How you accomplish that is not 
important (to me - speaking as an end user).

(Note: I understand the underlying issues somewhat - I'm just giving you 
a user's perspective).
>>> As cgf pointed out, Windows has zillions of error codes.  We wouldn't
>>> want to generate the same number of POSIX-like error codes.  It wouldn't
>>> make a lot of sense since POSIX applications only test for a limited,
>>> expected number of error codes, and it might break things.
>> I was talking error *messages* not error *codes*.
> Again, cause and effect turned upside down.
I don't think so.
Andrew DeFaria <>
Why do you park in a driveway and drive on a parkway?

Problem reports:
Unsubscribe info:

More information about the Cygwin mailing list