[uClibc]Re: pread/pwrite broken w/o large file support

Ronald Wahl rwa at peppercon.com
Thu Nov 14 10:27:36 UTC 2002


On Thu, 14 Nov 2002 03:18:04 -0700, Erik Andersen wrote:

> On Thu Nov 14, 2002 at 09:28:53AM +0100, Ronald Wahl wrote:
>> On 29 Jul 2002 15:03:09 +0200, Ronald Wahl wrote:
>> 
>> > On Mon, 15 Jul 2002 04:19:31 -0600, Erik Andersen wrote:
>> >> On Wed Jul 10, 2002 at 02:34:35AM -0700, David Blythe wrote:
>> >>> Sorry, i got distracted.  Attached is the patch (apply it from the libc 
>> >>> subdirectory).  You have to go back and set UNIFIED_SYSCALL to true in 
>> >>> the top level Config file.
>> 
>> >> Could you split this up for me.  I'm happy to appy the powerpc
>> >> UNIFIED_SYSCALL patch.  The other syscall renaming stuff I need
>> >> to look over more closely, but splitting things into several
>> >> distinct parts makes it much easier for me to review things... 
>> 
>> > Just a reminder: When will we have the unified syscall stuff for
>> > powerpc? Now since things are got splitted into a "common" and some
>> > system specific directories it should be easier i think.
>> 
>> What's up with this issue? This broken pread/pwrite stuff (on PPC) bugs
>> me from time to time. 

> Can you remind me of the problem?  I'm afraid whatever it is
> has apparently fallen completely off my todo list...

<cite author="David Blythe">
  Several of the 64 bit calls are busted in the ppc implementation. The
  powerpc must put an ll parameter in an odd,even register pair, so it
  leaves a hole to get to the next pair if necessary.  This can't be
  coded using the existing syscall macros in a machine independent way.
  I rewrote the ppc syscall implementation to use a version of the
  unified system call interface and bypassed the syscall macros
  altogether.  I still had to fix the [f]truncate64 wrapper that does
  the wrong thing for ppc (cf. glibc).  I'm not sure what you would do
  if you want to continue using the C syscall macros short of moving the
  implementation into the architecture-specific directories and coding
  by hand.

  I'll post a patch (against 9.11) with the unified syscall interface
  for ppc later today or tomorrow.
</cite>

The patch David had sent should be in the archive. I havn't tested this
code yet since the patch is against an old uclibc.

- ron



More information about the uClibc mailing list