problem with write() and a tie()d filehandle

[p5pRT]

Migrated from rt.perl.org#8149 (status was 'open')

Searchable as RT8149$

[p5pRT]

From abe@ztreet.demon.nl

Created by abe@ztreet.demon.nl

write() on a tie()d filehandle complains about an unopened filehandle.

The printf() on the that same tie()d filehandle works ok.

I looked at the documentation but couldn't find any mention of write() not beeing
supported.

This program demonstrates it (confirmed for ActivePerl 5.6.1 build 628).

#!perl
use warnings FATAL => 'all';
use strict;

{
package FakeOut;
sub TIEHANDLE { bless \( my $scalar ), shift; }
sub PRINT { my $self = shift; $$self .= shift; }
sub PRINTF {
my $self = shift;
my $fmt = shift;
$$self .= sprintf $fmt, @_;
}

}

my( $text, $numb );
format FAKEOUT =
@<<<<<<<<<< @>>>>>
$text, $numb
.

my $fake = tie *FAKEOUT, 'FakeOut';
foreach $text ( qw( one two three four five ) ) {
$numb = length $text;
# printf FAKEOUT "%-10s %5s\n", $text, $numb;
write FAKEOUT;
}

print $$fake;

__END__

write() on unopened filehandle FAKEOUT at tiedwrite.pl line 27.

Perl Info

Flags:
    category=core
    severity=low

Site configuration information for perl v5.7.2:

Configured by a.timmerman at Sat Dec 15 02:26:14 2001.

Summary of my perl5 (revision 5 undef) configuration:
  Platform:
    osname=MSWin32, osvers=4.0, archname=MSWin32-x86-multi-thread
    uname=''
    config_args='undef'
    hint=recommended, useposix=true, d_sigaction=undef
    usethreads=undef use5005threads=undef useithreads=define usemultiplicity=define
    useperlio=define d_sfio=undef uselargefiles=undef usesocks=undef
    use64bitint=undef use64bitall=undef uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cl', ccflags ='-nologo -Gf -W3 -O1 -MD -DNDEBUG -DWIN32 -D_CONSOLE
-DNO_STRICT -DHAVE_DES_FCRYPT   -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS
-DUSE_PERLIO -DPERL_MSVCRT_READFIX',
    optimize='-O1 -MD -DNDEBUG',
    cppflags='-DWIN32'
    ccversion='undef', gccversion='', gccosandvers='undef'
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=undef, longlongsize=8, d_longdbl=define, longdblsize=10
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=4
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='link', ldflags ='-nologo -nodefaultlib -release
-libpath:"c:\opt\perl572\lib\CORE"  -machine:x86'
    libpth=\lib
    libs=  oldnames.lib kernel32.lib user32.lib gdi32.lib winspool.lib  comdlg32.lib
advapi32.lib shell32.lib ole32.lib oleaut32.lib  netapi32.lib uuid.lib wsock32.lib
mpr.lib winmm.lib  version.lib odbc32.lib odbccp32.lib msvcrt.lib
    perllibs=undef
    libc=msvcrt.lib, so=dll, useshrplib=yes, libperl=perl57.lib
  Dynamic Linking:
    dlsrc=dl_win32.xs, dlext=dll, d_dlsymun=undef, ccdlflags=' '
    cccdlflags=' ', lddlflags='-dll -nologo -nodefaultlib -release
-libpath:"c:\opt\perl572\lib\CORE"  -machine:x86'

Locally applied patches:
    DEVEL13686


@INC for perl v5.7.2:
    c:/opt/perl572/lib
    c:/opt/perl572/site/lib
    .


Environment for perl v5.7.2:
    HOME (unset)
    LANG (unset)
    LANGUAGE (unset)
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)

PATH=c:\opt\perl572\bin;C:\WINNT\system32;C:\WINNT;C:\WINNT\system32\WBEM;C:\Perl\bin\;C:\usr\bin\;C:\usr\bin;C:\bin;C:\usr\local\bin;c:\usr\local\openssl\bin;C:\gcc-2.95.2\bin;C:\PROGRA~1\ULTRAE~1;C:\Program
Files\SecureCRT 3.0;C:\Program Files\Microsoft Visual
Studio\Common\MSDev98\Bin;C:\Program Files\Microsoft Visual
Studio\Common\Tools;C:\Program Files\Microsoft Visual Studio\VC98\bin
    PERLDOC_PAGER=less
    PERL_BADLANG (unset)
    SHELL (unset)

groetje,

Abe
-- 
perl -wle '%_=qw(Just Just another Perl Perl another hacker hacker);print join" ",map$_{$_}=>sort keys%_'

[p5pRT]

From @iabyn

still present in bleed@​20710

[p5pRT]

From @Hugmeir

Is this a bug? Wouldn't you have to define a WRITE method for the tied
handle for this to work?

--hugmeir

[p5pRT]

From @cpansprout

WRITE is for syswrite. If WRITE were for formats, then WRITE would have
to implement formats itself, which would not be very helpful.

Currently write() simply ignores the tiedness, just like stat (#112164).

And I’ve just discovered that printf won’t fall back to PRINT if PRINTF
is not defined, which is not very nice.

I’m now wondering whether tied filehandles could be implemented as an IO
layer instead. Then a lot of these things could Just Work. But I may
be drawing that conclusion prematurely.

--

Father Chrysostomos

[p5pRT]

From @Tux

On Sat, 26 May 2012 17​:48​:04 -0700, "Father Chrysostomos via RT"
<perlbug-followup@​perl.org> wrote​:

WRITE is for syswrite. If WRITE were for formats, then WRITE would have
to implement formats itself, which would not be very helpful.

WRITE is for syswrite, write is for write. confusing and heavyly
underdocumented

[toddr]

@Tux should this be closed?