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

[Ronald Wahl]

On 04 Jul 2002 09:01:07 +0200, Ronald Wahl wrote:

> On 04 Jul 2002 09:54:57 +0900, Miles Bader wrote:
>> presumably it would
>> have to be handled the same way truncate64 is, by explicitly splitting the
>> 64-bit argument into two 32-bit arguments on 32-bit architectures.

>> Does the glibc def really do the same thing?

> Ah, I looked wrong. :-/ For Linux you are right... It needs to be
> splitted (depending on byte order). But anyway - it needs to be fixed in
> uClibc.

Hmm, just tried splitting and it does not work for PowerPC. At least for
PowerPC my patch was correct: 

glibc-2.2.5/sysdeps/unix/sysv/linux/mips/pread.c:

...
static ssize_t __emulate_pread (int fd, void *buf, size_t count,
                                off_t offset) internal_function;
...

ssize_t
__libc_pread (fd, buf, count, offset)
     int fd;
     void *buf;
     size_t count;
     off_t offset;
{
  ssize_t result;

  /* First try the syscall.  */
  result = INLINE_SYSCALL (pread, 6, fd, CHECK_N (buf, count), count, 0,
                           __LONG_LONG_PAIR (0, offset));
# if __ASSUME_PREAD_SYSCALL == 0
  if (result == -1 && errno == ENOSYS)
    /* No system call available.  Use the emulation.  */
    result = __emulate_pread (fd, buf, count, offset);
# endif
  return result;
}
...

ron

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