RE: PATCH: Re: LFS notes RE: pws-18 is go

["Andrej Borsenkow" <borsenkow.msk@xxxxxx>]

>
> > 3. Setting LFS[64]_CFLAGS & Co is not enough!!! One must set either
> > _LARGEFILE_SOURCE *or* _LARGEFILE64_SOURCE to indicate, which
> mode is used
> > (a side note, that _LARGEFILE64_SOURCE has some problems on our system).
>
> Eh?  The LFS_CFLAGS getconf stuff just probes for the right flags to set.
> On Solaris 5.6 I get CPPFLAGS set to
> -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64
> Is the getconf test working where you are?  If not, none of this stuff
> applies anyway.
>

>From the page I quoted:

3.3.1 Compilation Environment - Visibility of Additions to the API
Applications which define the macro _LARGEFILE_SOURCE to be 1 before
inclusion of any header will enable at least the functionality described in
2.0 Changes to the Single UNIX Specification on implementations that support
these features. Implementations that support these features will define
_LFS_LARGEFILE to be 1 in <unistd.h>, as described in 3.1.2.12 <unistd.h>.

3.3.4 Utilities: Optional Method for Specifying the Size of an off_t
For programs to take advantage of different environments, it is necessary to
compile them for each particular environment. For programs to make use of
the features described in this section they must be compiled with new
compiler and linker options. The getconf utility called with the new
arguments can be used to generate compiler and linker options.
Example 1:

An example of compiling a program with a "large" off_t and that uses
fseeko() and ftello() and uses yacc:

   c89 -D_LARGEFILE_SOURCE     -o foo      \
        $(getconf LFS_CFLAGS)  y.tab.c b.o \
        $(getconf LFS_LDFLAGS)             \
        -ly $(getconf LFS_LIBS)
Example 2:
An example of compiling a program with a "large" off_t and that does not use
fseeko() and ftello() and has no application specific libraries:

   c89  $(getconf LFS_CFLAGS)  a.c         \
        $(getconf LFS_LDFLAGS)             \
        $(getconf LFS_LIBS)

A.3.2.1 Compilation Environment - Visibility of Additions to the API
Applications which use the fseeko() and ftello() interfaces should define
_LARGEFILE_SOURCE to be 1, then include <unistd.h> and then test that
_LFS_LARGEFILE is 1 to determine if the additional functionality is indeed
available. This additional functionality may be available even when
_LARGEFILE_SOURCE is not defined, but it will not be available to strictly
conforming X/Open programs.
This macro does not affect the size of off_t (see 3.3.3 Mixed API and
Compile Environments Within a Single Process).


In other words:

to use 64 bit off_t, one has to use LFS_CFLAGS
to use ftello/fseeko one must set _LARGEFILE_SOURCE
Solaris is non-conformant in automagically setting _LARGEFILE_SOURCE in
LFS_CFLAGS

>
> I've added this, but all you're supposed to do is set CPPFLAGS to
> anything,
> even empty, and it will suppress modification of all the flags by
> the large
> file check.
>

Hmm... I've tried it, but still got all LFS flags. I'll recheck it when I
have a bit more time.

/andrej