Filehandle Leak With Wrong binmode

[p5pRT]

Migrated from rt.perl.org#118957 (status was 'open')

Searchable as RT118957$

[p5pRT]

From @shlomif

Created by @shlomif

The following program (when run on Mageia Linux x86-64 Cauldron using
perl-5.18.0 from perlbrew and on other systems other people tried
on IRC) results at "Too many open files at hv.pl line 2."

for my $x (1 .. 10000) {
  open my $temp, '>', "/tmp/t" or die "$!";
  binmode $temp, "​:unix";
  close $temp;
}

The problem is due to the «binmode $temp, "​:unix";» which is wrong, but should
be handled more carefully.

This was reported by ais523 on Freenode's #perl, so thanks go to him/her.

Perl Info

Flags:
    category=core
    severity=low

Site configuration information for perl 5.18.0:

Configured by shlomif at Fri May 24 18:23:32 IDT 2013.

Summary of my perl5 (revision 5 version 18 subversion 0) configuration:
   
  Platform:
    osname=linux, osvers=3.8.13-desktop-1.mga3, archname=x86_64-linux
    uname='linux telaviv1.shlomifish.org 3.8.13-desktop-1.mga3 #1 smp tue may
14 19:05:25 utc 2013 x86_64 x86_64 x86_64 gnulinux ' config_args='-de
-Dprefix=/home/shlomif/apps/perl/brew/perls/perl-5.18.0
-Aeval:scriptdir=/home/shlomif/apps/perl/brew/perls/perl-5.18.0/bin'
hint=recommended, useposix=true, d_sigaction=define useithreads=undef,
usemultiplicity=undef useperlio=define, d_sfio=undef, uselargefiles=define,
usesocks=undef use64bitint=define, use64bitall=define, uselongdouble=undef
usemymalloc=n, bincompat5005=undef Compiler:
    cc='cc', ccflags ='-fno-strict-aliasing -pipe -fstack-protector
-I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
optimize='-O2', cppflags='-fno-strict-aliasing -pipe -fstack-protector
-I/usr/local/include' ccversion='', gccversion='4.7.2', gccosandvers=''
    intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
    ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t',
lseeksize=8 alignbytes=8, prototype=define
  Linker and Libraries:
    ld='cc', ldflags =' -fstack-protector -L/usr/local/lib'
    libpth=/usr/local/lib /lib/../lib64 /usr/lib/../lib64 /lib /usr/lib /lib64 /usr/lib64 /usr/local/lib64
    libs=-lnsl -lgdbm -ldb -ldl -lm -lcrypt -lutil -lc -lgdbm_compat
    perllibs=-lnsl -ldl -lm -lcrypt -lutil -lc
    libc=/lib/libc-2.17.so, so=so, useshrplib=false, libperl=libperl.a
    gnulibc_version='2.17'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
    cccdlflags='-fPIC', lddlflags='-shared -O2 -L/usr/local/lib
-fstack-protector'

Locally applied patches:
    


@INC for perl 5.18.0:
    /home/shlomif/apps/perl/modules/lib/perl5/site_perl/5.18.0
    /home/shlomif/apps/perl/modules/lib/perl5/site_perl/5.16.3
    /home/shlomif/apps/perl/modules/lib/site_perl/5.18.0
    /home/shlomif/apps/perl/modules/lib/site_perl/5.16.3
    /home/shlomif/apps/perl/modules/lib/perl5/5.18.0
    /home/shlomif/apps/perl/modules/lib/perl5/5.16.3
    /home/shlomif/apps/perl/brew/perls/perl-5.18.0/lib/site_perl/5.18.0/x86_64-linux
    /home/shlomif/apps/perl/brew/perls/perl-5.18.0/lib/site_perl/5.18.0
    /home/shlomif/apps/perl/brew/perls/perl-5.18.0/lib/5.18.0/x86_64-linux
    /home/shlomif/apps/perl/brew/perls/perl-5.18.0/lib/5.18.0
    .


Environment for perl 5.18.0:
    HOME=/home/shlomif
    LANG=en_GB.UTF-8
    LANGUAGE=en_GB:en
    LC_ADDRESS=en_US.UTF-8
    LC_COLLATE=en_US.UTF-8
    LC_CTYPE=en_US.UTF-8
    LC_IDENTIFICATION=en_GB.UTF-8
    LC_MEASUREMENT=en_GB.UTF-8
    LC_MESSAGES=en_US.UTF-8
    LC_MONETARY=en_US.UTF-8
    LC_NAME=en_GB.UTF-8
    LC_NUMERIC=en_GB.UTF-8
    LC_PAPER=en_US.UTF-8
    LC_SOURCED=1
    LC_TELEPHONE=en_US.UTF-8
    LC_TIME=en_GB.UTF-8
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=/home/shlomif/apps/perl/brew/bin:/home/shlomif/apps/perl/brew/perls/perl-5.18.0/bin:/home/shlomif/apps/gwenview/bin:/home/shlomif/apps/perl/modules/local/bin:/home/shlomif/apps/perl/modules/bin:/opt/valgrind-trunk/bin:/home/shlomif/apps/latemp/bin:/home/shlomif/apps/quadpres/bin:/home/shlomif/apps/wml/bin:/home/shlomif/bin:/home/shlomif/bin:/home/shlomif/apps/gwenview/bin:/usr/local/bin:/usr/bin:/usr/games:/usr/lib64/qt4/bin
    PERL5LIB=/home/shlomif/apps/perl/modules/lib/perl5/site_perl/5.18.0:/home/shlomif/apps/perl/modules/lib/perl5/site_perl/5.16.3:/home/shlomif/apps/perl/modules/lib/site_perl/5.18.0:/home/shlomif/apps/perl/modules/lib/site_perl/5.16.3:/home/shlomif/apps/perl/modules/lib/perl5/5.18.0:/home/shlomif/apps/perl/modules/lib/perl5/5.16.3
    PERLBREW_BASHRC_VERSION=0.58
    PERLBREW_HOME=/home/shlomif/.perlbrew
    PERLBREW_MANPATH=/home/shlomif/apps/perl/brew/perls/perl-5.18.0/man
    PERLBREW_PATH=/home/shlomif/apps/perl/brew/bin:/home/shlomif/apps/perl/brew/perls/perl-5.18.0/bin
    PERLBREW_PERL=perl-5.18.0
    PERLBREW_ROOT=/home/shlomif/apps/perl/brew
    PERLBREW_VERSION=0.64
    PERL_AUTOINSTALL=--skipdeps --alldeps
    PERL_BADLANG (unset)
    PERL_MM_USE_DEFAULT=1
    SHELL=/bin/bash

[p5pRT]

From @jkeenan

On Sun Jul 21 08​:56​:29 2013, shlomif@​shlomifish.org wrote​:

This is a bug report for perl from shlomif@​iglu.org.il,
generated with the help of perlbug 1.39 running under perl 5.18.0.

-----------------------------------------------------------------
[Please describe your issue here]

The following program (when run on Mageia Linux x86-64 Cauldron using
perl-5.18.0 from perlbrew and on other systems other people tried
on IRC) results at "Too many open files at hv.pl line 2."

for my $x (1 .. 10000) {
open my $temp, '>', "/tmp/t" or die "$!";
binmode $temp, "​:unix";
close $temp;
}

The problem is due to the �binmode $temp, "​:unix";� which is wrong,
but should
be handled more carefully.

Apart from the fact that it results in this error, what is "wrong" about
qq{binmode $temp, "​:unix"}?

Incidentally, on my Linode the threshold for triggering this problem was​:
1020​: success
1021​: error message as reported

Thank you very much.
Jim Keenan

[p5pRT]

The RT System itself - Status changed from 'new' to 'open'

[p5pRT]

From @Leont

On Mon, Jul 22, 2013 at 1​:58 AM, James E Keenan via RT
<perlbug-followup@​perl.org> wrote​:

Apart from the fact that it results in this error, what is "wrong" about
qq{binmode $temp, "​:unix"}?

:unix always acts as a bottom layer. So pushing it on top of an
existing handle will make it (mostly) ignore the existing layers.

Incidentally, on my Linode the threshold for triggering this problem was​:
1020​: success
1021​: error message as reported

Given you start with 3 open fd's that aligns with a fd-max of 1024

Leon

[Leont]

Fixed in #17489