@@GLIBC_2.1

Stuart Anderson anderson at metrolink.com
Mon Nov 8 14:09:05 PST 1999



Appearantly, the fdopen implementation (and several other things) changed
between glibc 2.0 and 2.1. The @@GLIBC_X.X indicates which behavior you get.

I think there may be some global variable that lives in the application that
says which version it was linked against, but I'm not sure of the details (but
need to learn & document it).

The mangle section of the specification is for this type of thing. The source
signature 

FILE * fdopen(int fildes, const char *mode)

is mangled to

FOO * fdopen@@GLIBC_2.0(..????..)

Again, I haven't figured out all of the details, but need to before our
next meeting.

On Mon, 8 Nov 1999 gk4 at us.ibm.com wrote:

> 
> 
> While trying to inventory the APIs and libraries used by applications such
> as StarOffice51 and WordPerfect8 I have stumbled across some redundant APIs
> with @GLIBC_2.0 and @@GLIBC_2.1 suffixes on RedHat 6.0.   So, for example,
> if I look at Netscape Communicator 4.7 I see that "fdopen" is undefined and
> needs to be resolved.
> 
> [gk4 at act5 gk4]$ nm -D -g /usr/local/netscape/netscape | grep fdopen
>          U fdopen
> 
> Looking at what libraries are dynamically linked, I see libc.so.6 is linked
> to netscape to resolve "fdopen".
> 
> [gk4 at act5 gk4]$ ldd /usr/local/netscape/netscape
>         libBrokenLocale.so.1 => /lib/libBrokenLocale.so.1 (0x40018000)
>         libXt.so.6 => /usr/X11R6/lib/libXt.so.6 (0x4001a000)
>         libSM.so.6 => /usr/X11R6/lib/libSM.so.6 (0x40064000)
>         libICE.so.6 => /usr/X11R6/lib/libICE.so.6 (0x4006e000)
>         libXmu.so.6 => /usr/X11R6/lib/libXmu.so.6 (0x40083000)
>         libXpm.so.4 => /usr/X11R6/lib/libXpm.so.4 (0x40095000)
>         libXext.so.6 => /usr/X11R6/lib/libXext.so.6 (0x400a2000)
>         libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x400ad000)
>         libdl.so.2 => /lib/libdl.so.2 (0x4014a000)
>         libstdc++-libc6.1-1.so.2 => /usr/lib/libstdc++-libc6.1-1.so.2
> (0x4014d000)
>         libm.so.6 => /lib/libm.so.6 (0x40190000)
>         libc.so.6 => /lib/libc.so.6 (0x401ac000)
>         /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)
> 
> However, when I look in libc.so.6 I see two "fdopen" definitions with
> either a @GLIBC_2.0 or @@GLIBC_2.1 suffix!
> 
> [gk4 at act5 gk4]$ nm -g /lib/libc.so.6 | grep fdopen
> 00050ae0 T _IO_fdopen@@GLIBC_2.1
> 00053410 T _IO_fdopen at GLIBC_2.0
> 00050ae0 T fdopen@@GLIBC_2.1
> 00053410 T fdopen at GLIBC_2.0
> 
> How is "fdopen" being resolved?  What is the purpose of the @GLIBC_2.0 or
> @@GLIBC_2.1 suffixes?
> 
> George Kraft IV
> gk4 at us.ibm.com
> 512-838-2688; t/l 678-2688
> Linux Technology Center
> IBM, Austin Texas
> 
> 
> 
> -- 
> To UNSUBSCRIBE, email to lsb-discuss-request at lists.linuxbase.org
> with subject of "unsubscribe". Trouble? Email listmaster at lists.linuxbase.org
> 


                                Stuart

Stuart R. Anderson                               anderson at metrolink.com

Metro Link Incorporated                          South Carolina Office
4711 North Powerline Road                        129 Secret Cove Drive
Fort Lauderdale, Florida 33309                   Lexington, SC 29072
voice: 954.938.0283                              voice: 803.951.3630
fax:   954.938.1982                              SkyTel: 800.405.3401
http://www.metrolink.com/



More information about the lsb-discuss mailing list