Re: [dpdk-dev] [PATCH] eal/linux: fix build

["Qiu, Michael" <michael.qiu@intel.com>]

On 3/4/2015 6:24 AM, Thomas Monjalon wrote:
>>> Compilation fails in some distributions because of missing unistd.h
>>> needed for pread/pwrite (seen with Suse):
>>>         lib/librte_eal/linuxapp/eal/eal_pci_uio.c:62:2:
>>>         error: implicit declaration of function ‘pread’
>>>
>>> Fixes: 4a499c649590 ("eal/linux: enable uio_pci_generic support")
>>>
>>> Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>
>> Acked-by: David Marchand <david.marchand@6wind.com>
> Applied

Hi, Thomas

This patch may be need to be reverted, as the error still exists.

suse-11-sp3-32:~/dpdk # uname -a
Linux suse-11-sp3-32 3.0.76-0.11-pae #1 SMP Fri Jun 14 08:21:43 UTC 2013
(ccab990) i686 i686 i386 GNU/Linux

suse-11-sp3-32:~/dpdk # gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/i686-pc-linux-gnu/4.5.1/lto-wrapper
Target: i686-pc-linux-gnu
Configured with: ./configure
Thread model: posix
gcc version 4.5.1 (GCC)

As I try to check the manual of pread, find that it has two:
----------------------------------------------------------
Man: find all matching manual pages
 * pread (2)
   pread (3p)
Man: What manual page do you want?
Man:
-------------------------------------------------------------
PREAD(2)                                                         Linux
Programmer's
Manual                                                        PREAD(2)



NAME
       pread, pwrite - read from or write to a file descriptor at a
given offset

SYNOPSIS
       #define _XOPEN_SOURCE 500

       #include <unistd.h>

       ssize_t pread(int fd, void *buf, size_t count, off_t offset);

       ssize_t pwrite(int fd, const void *buf, size_t count, off_t offset);

--------------------------------------------------------------------------------------------------------------------------------------------

READ(3P)                                                         POSIX
Programmer's
Manual                                                        READ(3P)



PROLOG
       This  manual page is part of the POSIX Programmer's Manual.  The
Linux implementation of this interface may differ (consult the
corresponding Linux
       manual page for details of Linux behavior), or the interface may
not be implemented on Linux.

NAME
       pread, read - read from a file

SYNOPSIS
       #include <unistd.h>



       ssize_t pread(int fildes, void *buf, size_t nbyte, off_t offset);
       ssize_t read(int fildes, void *buf, size_t nbyte);


DESCRIPTION

------------------------------------------------------------------------------------------------------------------------------------------

While I try to add marco #define _XOPEN_SOURCE 500

Other errors show up

Who knows how to solve this issue?

Thanks,
Michael

>