From Mark.Martinec@ijs.si

This is a bug report for perl from Mark.Martinec@​ijs.si,
generated with the help of perlbug 1.36 running under perl 5.10.0.

The readline() function (or a diamond I/O operator <>) returns
a EBADF (Bad file descriptor) as its errno status on end-of-file
when PERLIO is set to "stdio" (which unfortunately is a default
setting in some Linux distributions).

The situation worsened with 5.10.0 (compared to 5.8.8)​:

$ echo "test" | PERLIO="stdio" perl5.8.8 -e \
  'for($!=0; &lt;&gt;; $!=0){print}; $!==0 or die "Err​: $!"'
test

$ echo "test" | PERLIO="stdio" perl5.10.0 -e \
  'for($!=0; &lt;&gt;; $!=0){print}; $!==0 or die "Err​: $!"'
test
Err​: Bad file descriptor at -e line 1, <> line 1.

This used to be an issue only on some Linux distributions
and not on FreeBSD. Now with 5.10.0 it happens here too.
The problem only occurs with PERLIO="stdio", not with an
unset PERLIO or with PERLIO="perlio".

The bug lures application programmers to ignore I/O status,
which is a bad programming practice and can lead to
hard-to-diagnose secondary application failures.
This is causing grief in at least two projects currently.
It would be really nice to get the status reporting right.

Btw, it is a probably related to bug #39060 (regarding non-NL
terminated last line), although missing last NL adds it own
quirk and perhaps still merits its own bug entry.
Now even with PERLIO="perlio" (or unset)​:

# line terminated with a NL
$ echo "test" | perl5.10.0 -e \
  'for($!=0; &lt;&gt;; $!=0){print}; $!==0 or die "Err​:$!"'
test

# line not terminated with a NL
$ echo -n "test" | perl5.10.0 -e \
  'for($!=0; &lt;&gt;; $!=0){print}; $!==0 or die "Err​:$!"'
Err​:Bad file descriptor at -e line 1, <> line 1.
test

Flags​:
  category=core
  severity=medium

Site configuration information for perl 5.10.0​:

Configured by mark at Fri Sep 26 14​:12​:03 UTC 2008.

Summary of my perl5 (revision 5 version 10 subversion 0) configuration​:
  Platform​:
  osname=freebsd, osvers=7.0-release-p1, archname=amd64-freebsd
  uname='freebsd neli-virtual.ijs.si 7.0-release-p1 freebsd 7.0-release-p1 #0​: sun jun 1 03​:02​:30 cest 2008
lesi@​neli.ijs.si​:usrobjusrsrcsysneli amd64 '
  config_args='-ds -e'
  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 ='-DHAS_FPSETMASK -DHAS_FLOATINGPOINT_H -fno-strict-aliasing -pipe -I/usr/local/include',
  optimize='-O',
  cppflags='-DHAS_FPSETMASK -DHAS_FLOATINGPOINT_H -fno-strict-aliasing -pipe -I/usr/local/include'
  ccversion='', gccversion='4.2.1 20070719 [FreeBSD]', 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 ='-Wl,-E -L/usr/local/lib'
  libpth=/usr/lib /usr/local/lib
  libs=-lm -lcrypt -lutil -lc
  perllibs=-lm -lcrypt -lutil -lc
  libc=, so=so, useshrplib=false, libperl=libperl.a
  gnulibc_version=''
  Dynamic Linking​:
  dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags=' '
  cccdlflags='-DPIC -fPIC', lddlflags='-shared -L/usr/local/lib'

Locally applied patches​:
 

@​INC for perl 5.10.0​:
  /usr/local/lib/perl5/5.10.0/amd64-freebsd
  /usr/local/lib/perl5/5.10.0
  /usr/local/lib/perl5/site_perl/5.10.0/amd64-freebsd
  /usr/local/lib/perl5/site_perl/5.10.0
  /usr/local/lib/perl5/site_perl/5.6.2.OFF
  /usr/local/lib/perl5/site_perl
  .

Environment for perl 5.10.0​:
  HOME=/root
  LANG (unset)
  LANGUAGE (unset)
  LD_LIBRARY_PATH (unset)
  LOGDIR (unset)
  PATH=/usr/local/zenoss/bin​:/usr/local/bin​:/usr/local/sbin​:/bin​:/sbin​:/usr/bin​:/usr/sbin
  PERL_BADLANG (unset)
  SHELL=/usr/local/bin/bash
�

From @nwc10

Dave notes​:

appears to be a regression since 5.8.8

@nwc10 - Status changed from 'new' to 'open'

From p5p@spam.wizbit.be

On Thu Oct 02 03​:10​:45 2008, mmartinec wrote​:

This is a bug report for perl from Mark.Martinec@​ijs.si,
generated with the help of perlbug 1.36 running under perl 5.10.0.

-----------------------------------------------------------------
The readline() function (or a diamond I/O operator <>) returns
a EBADF (Bad file descriptor) as its errno status on end-of-file
when PERLIO is set to "stdio" (which unfortunately is a default
setting in some Linux distributions).

The situation worsened with 5.10.0 (compared to 5.8.8)​:

$ echo "test" | PERLIO="stdio" perl5.8.8 -e \
'for($!=0; &lt;&gt;; $!=0){print}; $!==0 or die "Err​: $!"'
test

$ echo "test" | PERLIO="stdio" perl5.10.0 -e \
'for($!=0; &lt;&gt;; $!=0){print}; $!==0 or die "Err​: $!"'
test
Err​: Bad file descriptor at -e line 1, <> line 1.

This used to be an issue only on some Linux distributions
and not on FreeBSD. Now with 5.10.0 it happens here too.
The problem only occurs with PERLIO="stdio", not with an
unset PERLIO or with PERLIO="perlio".

The bug lures application programmers to ignore I/O status,
which is a bad programming practice and can lead to
hard-to-diagnose secondary application failures.
This is causing grief in at least two projects currently.
It would be really nice to get the status reporting right.

Btw, it is a probably related to bug #39060 (regarding non-NL
terminated last line), although missing last NL adds it own
quirk and perhaps still merits its own bug entry.
Now even with PERLIO="perlio" (or unset)​:

# line terminated with a NL
$ echo "test" | perl5.10.0 -e \
'for($!=0; &lt;&gt;; $!=0){print}; $!==0 or die "Err​:$!"'
test

# line not terminated with a NL
$ echo -n "test" | perl5.10.0 -e \
'for($!=0; &lt;&gt;; $!=0){print}; $!==0 or die "Err​:$!"'
Err​:Bad file descriptor at -e line 1, <> line 1.
test

-----------------------------------------------------------------

For me this happens with perl-5.8.1+. (on linux)

Binary search with PERLIO=stdio​:

----Program----
#!/usr/bin/perl

system( qq#echo "test" | PERLIO="stdio" $^X -e 'for(\$!=0; <>;
\$!=0){print}; \$!==0 or die "Err​: \$!"'#);

----Output of .../ptWpY1t/perl-5.8.0@​19461/bin/perl----
test

----EOF ($?='0')----
----Output of .../pP1BToL/perl-5.8.0@​19462/bin/perl----
Err​: Invalid argument at -e line 1, <> line 1.
test

----EOF ($?='0')----
Need a perl between 19461 and 19462

http​://public.activestate.com/cgi-bin/perlbrowse/p/19462
Change 19462 by jhi@​kosh on 2003/05/09 18​:53​:27

  Try to comprehensively have a plan B if a PerlIO
  layer doesn't have a particular function.
  (1) If there's a corresponding PerlIOBase, call it.
  (2) If not having the function is 'harmless', be silently happy.
  (Currently only Flush is in this category.)
  (3) Otherwise set errno and return failure.

A binary search with PERLIO=perlio and without a newline​:
----Program----
#!/usr/bin/perl

system( qq#echo -n "test" | PERLIO="perlio" $^X -e 'for(\$!=0; <>;
\$!=0){print}; \$!==0 or die "Err​: \$!"'#);

----Output of .../ptWpY1t/perl-5.8.0@​19461/bin/perl----
test
----EOF ($?='0')----
----Output of .../pP1BToL/perl-5.8.0@​19462/bin/perl----
Err​: Invalid argument at -e line 1, <> line 1.
test
----EOF ($?='0')----
Need a perl between 19461 and 19462

Best regards,

Bram

From @rgs

Solved by d7dfc38

@rgs - Status changed from 'open' to 'resolved'