From: Heesob Park <phasis@...>
Date: 2008-08-29T11:04:49+09:00
Subject: Re: Unraveling binary data out of the proc filesystem on Solaris

2008/8/29 Daniel Berger <djberg96@gmail.com>:
>
>
> On Aug 28, 7:37 pm, "Heesob Park" <pha...@gmail.com> wrote:
>> 2008/8/26 Daniel Berger <djber...@gmail.com>:
>>
>> > On Aug 25, 7:59 pm, "Heesob Park" <pha...@gmail.com> wrote:
>> >> Hi,
>>
>> >> 2008/8/26 Daniel Berger <djber...@gmail.com>:
>>
>> <snip>>
>> >> I guess you should use lseek and read combination.
>>
>> > Ruby has no lseek that I'm aware of. I tried an open + seek + read
>> > approach, but I get the same result.
>>
>> Are you unaware IO#sysseek ? sysseek is actualy lseek.
>>
>> ------------------------------------------------------------- IO#sysseek
>>      ios.sysseek(offset, whence=SEEK_SET)   => integer
>> ------------------------------------------------------------------------
>>      Seeks to a given _offset_ in the stream according to the value of
>>      _whence_ (see +IO#seek+ for values of _whence_). Returns the new
>>      offset into the file.
>>
>>         f = File.new("testfile")
>>         f.sysseek(-13, IO::SEEK_END)   #=> 53
>>         f.sysread(10)                  #=> "And so on."
>>
>> I guess open + sysseek +sysread will work for you.
>
> I tried sysseek on RHEL, but couldn't make it work. It's possible I
> did something wrong, but I'm not sure what.
>
> I also see nothing in the lseek or sysseek documentation that says it
> doesn't move the file pointer.
>
Did you check replacing pread with lseek and read combination in C
code implementation not working? If then pread is the only way.


Regards,

Park Heesob