From: Daniel Berger <djberg96@...>
Date: 2008-09-13T02:28:13+09:00
Subject: Re: Strange Errno::EOVERFLOW error with IO#read and IO#sysread

On Sep 12, 11:11 am, "ara.t.howard" <ara.t.how...@gmail.com> wrote:
> On Sep 12, 2008, at 10:48 AM, Daniel Berger wrote:
>
>
>
> > Hi all,
>
> > Ruby 1.8.6 p114 (32-bit)
> > Solaris 10
>
> > I'm reading binary data out of the /proc/<pid>/as file on Solaris, and
> > I'm hitting a curious overflow error on one process in particular:
>
> > # With IO#sysread
> > irb(main):010:0> File.open("/proc/383/as"){ |fh| fh.sysread(4) }
> > Errno::EOVERFLOW: Value too large for defined data type - /proc/383/as
> >        from (irb):10:in `sysread'
> >        from (irb):10
> >        from (irb):10:in `open'
> >        from (irb):10
>
> > # With IO#read
> > rb(main):010:0> File.open("/proc/383/as"){ |fh| fh.read(4) }
> > Errno::EOVERFLOW: Value too large for defined data type - /proc/383/as
> >        from (irb):10:in `read'
> >        from (irb):10
> >        from (irb):10:in `open'
> >        from (irb):10
>
> > Where pid 383 is:
>
> > UID   PID  PPID   C    STIME TTY         TIME CMD
> > root   383     1   0 07:14:42 ?           0:01 /usr/sfw/sbin/snmpd
>
> > This is the only pid in particular where this error occurs (out of
> > about 80).
>
> > Any idea what's happening here?
>
> > Thanks,
>
> > Dan
>
> your programs are so powerful daniel - they're overwhelming the
> system!  maybe if you re-write in perl the system will be able to
> handle them.

Nope:

use strict;
use warnings;

my $file = "/proc/383/as";

open(FH, $file) or die $!;

my $buf = "";

# Dies here with: Value too large for defined data type
read(FH, $buf, 4, 0) or die $!;

close(FH);

Regards,

Dan