Re: [RFC] fseek, an alternative implementation (PR22359)

[Brooks Moses <brooks dot moses at codesourcery dot com>]

Daniel Franke wrote:
> While working on the docs last week, I learned, that the FSEEK intrinsic is 
> not implemented yet. 
>
> The FSEEK implementation of g77 takes a statement label to jump to, if an 
> error occurs. Since there is no other intrinsic that takes a statement label, 
> considerable effort would be necessary to implement the framework needed. As 
> demand is low (one PR, no dupes, no usage of FSEEK shown by google-code 
> search), it might be worthwile to implement the FSEEK intrinsic for 
> completeness and replace the statement label by a status flag:
>
>   g77:        CALL FSEEK(unit, offset, whence, *100)
>   gfortran:   CALL FSEEK(unit, offset, whence, status)
>               IF (status /= 0) goto 100
>
> This is not 100% compability, but reasonable close.

I agree that this is the right way to do this.  (I think there was 
actually a fair bit of discussion on the mailing list about this, some 
months ago, and I'm pretty sure this was the conclusion we reached then 
as well.)

The infrastructure to put an alternate return -- and an optional one, no 
less! -- in an intrinsic function is very definitely not worth it just 
for this one function.

- Brooks