Re: [bug-gawk] GNU Libc2.27 and stdio streams

[arnold]

Hi Nelson.

The discussion here was about adding an "abort" statement to gawk that
would be like "exit", but would not run the END rules.

HOWEVER, your information about 2.27 is helpful; I have added
fflush(NULL) in front of each actual abort() call in the code and
will push the change out soon.

Thanks!

Arnold

"Nelson H. F. Beebe" <address@hidden> wrote:

> A posting on the address@hidden list a few minutes ago reported:
>
> >> ...
> >> As Gnu libc 2.27 comes online, keep aware that [it] no longer attempts
> >> to flush stdio streams on abort.  I wonder if this `might' affect
> >> Guile error messages that occur at abort.
> >> ...
>
> There have been several recent discussions on the bug-gawk list about
> the abort() call, so that heads-up might require a small defensive
> coding response.
>
> I suppose that some might view an abort() call mean to "get me out of
> here, NOW!  and I don't care how you do, just DO IT".
>
> On the other hand, output buffer flushing is likely usually harmless,
> and reduces user surprise.  Perhaps the glibc developer list should be
> consulted to understand why they made that change.
>
> I checked my copy of POSIX (the IEEE Std 1003.1-2001 version), and
> found little mention of abort(), and nothing on its desired behavior.
>
> Here is what a 2007 draft of the ISO C Standard (ISO/IEC 9899:TC3)
> says:
>
> >> ...
> >>     7.20.4.1 The abort function
> >>     Synopsis
> >> 1          #include <stdlib.h>
> >>            void abort(void);
> >>     Description
> >> 2   The abort function causes abnormal program termination to occur, 
> >> unless the signal
> >>     SIGABRT is being caught and the signal handler does not return. 
> >> Whether open streams
> >>     with unwritten buffered data are flushed, open streams are closed, or 
> >> temporary files are
> >>     removed is implementation-defined. An implementation-defined form of 
> >> the status
> >>     unsuccessful termination is returned to the host environment by means 
> >> of the function
> >>     call raise(SIGABRT).
> >>     Returns
> >> 3   The abort function does not return to its caller.
> >> ...
>
> Thus, the glibc changes are standard conforming in this area.
>
> -------------------------------------------------------------------------------
> - Nelson H. F. Beebe                    Tel: +1 801 581 5254                  
> -
> - University of Utah                    FAX: +1 801 581 4148                  
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