develooper Front page | perl.perl5.porters | Postings from January 2019

[perl #121033] [PATCH] Document read/write-only undef open

From:
Tony Cook via RT
Date:
January 22, 2019 08:02
Subject:
[perl #121033] [PATCH] Document read/write-only undef open
Message ID:
rt-4.0.24-25771-1548144131-1675.121033-15-0@perl.org
On Tue, 01 Jan 2019 21:02:28 -0800, tonyc wrote:
> On Thu, 23 Jan 2014 04:28:39 -0800, tobyink wrote:
> > How about this text?
> >
> > """
> > As a special case the three-argument form with the third argument
> > being C<undef>:
> >
> > open(my $tmp, "+>", undef) or die ...
> >
> > opens a filehandle to an anonymous temporary file. An anonymous file
> > can be opened in any mode, but opening it in read-write mode is
> > likely
> > to be the most useful. (If the file is open in read-write mode, you
> > can write to it, then C<seek()> to the beginning of the file, and
> > read
> > back from it.)
> > """
> 
> 
> 32458de9a4322bd2e66c525d33720a42df7e0b56 introduced something similar
> to this:
> 
> This now reads:
> 
> As a special case the three-argument form with a read/write mode and
> the third
> argument being L<C<undef>|/undef EXPR>:
> 
> open(my $tmp, "+>", undef) or die ...
> 
> opens a filehandle to a newly created empty anonymous temporary file.
> (This happens under any mode, which makes C<< +> >> the only useful
> and
> sensible mode to use.)  You will need to
> L<C<seek>|/seek FILEHANDLE,POSITION,WHENCE> to do the reading.

Presumably that's enough, so closing.

Tony

---
via perlbug:  queue: perl5 status: open
https://rt.perl.org/Ticket/Display.html?id=121033



nntp.perl.org: Perl Programming lists via nntp and http.
Comments to Ask Bjørn Hansen at ask@perl.org | Group listing | About