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[perl #112826] Tie::StdHandle read() offset argument
# New Ticket Created by Kevin Ryde
# Please include the string: [perl #112826]
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With debian packaged perl 5.14.2 and Tie::StdHandle version 4.2, the
"offset" argument to read() is not obeyed by a tied handle. For example

use strict;
use Tie::StdHandle;
open PP, '</dev/null';
my $buf = "xxxxxxxxxx\n";
read PP, $buf, 2, 5;
print "plain: \"$buf\"\n";
tie *TT, 'Tie::StdHandle', '</dev/null';
my $buf = "xxxxxxxxxx\n";
read TT, $buf, 2, 5;
print "StdHandle: \"$buf\"\n";
exit 0;


plain: "xxxxx"
StdHandle: ""

where I expected StdHandle to leave $buf as "xxxxx" the same as a plain

Perhaps the READ method should notice an offset argument and pass it on
to the real read(). I get some joy from the following. Prototyping
prevents passing @_ directly does it?, the same as done in OPEN().

sub READ {
(@_ > 3
? read($_[0],$_[1],$_[2],$_[3])
: read($_[0],$_[1],$_[2]))

[Please do not change anything below this line]
Site configuration information for perl 5.14.2:

Configured by Debian Project at Sat Mar 3 16:40:46 UTC 2012.

Summary of my perl5 (revision 5 version 14 subversion 2) configuration:

osname=linux, osvers=2.6.32-5-686-bigmem, archname=i486-linux-gnu-thread-multi-64int
uname='linux murphy 2.6.32-5-686-bigmem #1 smp mon jan 16 16:42:05 utc 2012 i686 gnulinux '
config_args='-Dusethreads -Duselargefiles -Dccflags=-DDEBIAN -D_FORTIFY_SOURCE=2 -g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Wformat-security -Werror=format-security -Dldflags= -Wl,-z,relro -Dlddlflags=-shared -Wl,-z,relro -Dcccdlflags=-fPIC -Darchname=i486-linux-gnu -Dprefix=/usr -Dprivlib=/usr/share/perl/5.14 -Darchlib=/usr/lib/perl/5.14 -Dvendorprefix=/usr -Dvendorlib=/usr/share/perl5 -Dvendorarch=/usr/lib/perl5 -Dsiteprefix=/usr/local -Dsitelib=/usr/local/share/perl/5.14.2 -Dsitearch=/usr/local/lib/perl/5.14.2 -Dman1dir=/usr/share/man/man1 -Dman3dir=/usr/share/man/man3 -Dsiteman1dir=/usr/local/man/man1 -Dsiteman3dir=/usr/local/man/man3 -Duse64bitint -Dman1ext=1 -Dman3ext=3perl -Dpager=/usr/bin/sensible-pager -Uafs -Ud_csh -Ud_ualarm -Uusesfio -Uusenm -Ui_libutil -DDEBUGGING=-g -Doptimize=-O2 -Duseshrplib -des'
hint=recommended, useposix=true, d_sigaction=define
useithreads=define, usemultiplicity=define
useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
use64bitint=define, use64bitall=undef, uselongdouble=undef
usemymalloc=n, bincompat5005=undef
cc='cc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fstack-protector -fno-strict-aliasing -pipe -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
optimize='-O2 -g',
cppflags='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fstack-protector -fno-strict-aliasing -pipe -I/usr/local/include'
ccversion='', gccversion='4.6.2', gccosandvers=''
intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=12345678
d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
ivtype='long long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
alignbytes=4, prototype=define
Linker and Libraries:
ld='cc', ldflags =' -fstack-protector -L/usr/local/lib'
libpth=/usr/local/lib /lib/i386-linux-gnu /lib/../lib /usr/lib/i386-linux-gnu /usr/lib/../lib /lib /usr/lib
libs=-lgdbm -lgdbm_compat -ldb -ldl -lm -lpthread -lc -lcrypt
perllibs=-ldl -lm -lpthread -lc -lcrypt
libc=, so=so, useshrplib=true,
Dynamic Linking:
dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
cccdlflags='-fPIC', lddlflags='-shared -L/usr/local/lib -fstack-protector'

Locally applied patches: