I'm not sure which library file the code is in though. For most things it's not needed.

?I have tried libc.so and it doesn't contains _strdup, amybe it's strdup instead I will try. Anyway I have a little question (a windowsian question :) ). Under windows I have a tool named "depends.exe" with it, I can sse what is exposed thru a dll, is there any equivalent under linux ? Arnaud -------------------------------------------------- From: "Eric Blake" <eblake(a)redhat.com&gt; Sent: Tuesday, October 19, 2010 2:15 PM To: "Justin Clift" <jclift(a)redhat.com&gt; Cc: <libvir-list(a)redhat.com&gt; Subject: Re: [libvirt] libvirt library binary name for linux > On 10/19/2010 06:07 AM, Justin Clift wrote: >> I'm not sure which library file the code is in though. For most >> things it's not needed. > > glibc (that is, libc.so, which is pretty much universally linked in to > every other program already). You don't need to add -lc to your compiler > line, at any rate. > > -- > Eric Blake eblake(a)redhat.com +1-801-349-2682 > Libvirt virtualization library http://libvirt.org > > -- > libvir-list mailing list > libvir-list(a)redhat.com > https://www.redhat.com/mailman/listinfo/libvir-list > -- libvir-list mailing list libvir-list(a)redhat.com https://www.redhat.com/mailman/listinfo/libvir-list

On 10/19/2010 11:31 PM, arnaud.champion(a)devatom.fr wrote: > > ?Okay, I have found it, I must use "libc.so.6" and the function name is > strdup not _strdup... > > So, it push to an other questions : > > Is libc.so.6 present on any linux distro ? (I use a fedora 13 here) It's a very standard library.  Sometimes it is "libc.so.6", on older Linux's, it can be "libc.so.5". You are generally safe to use it. :)

On 10/20/2010 12:03 AM, Alejandro Mery wrote: <snip> >> It's a very standard library. Sometimes it is "libc.so.6", on older >> Linux's, it can be "libc.so.5". >> >> You are generally safe to use it. :) > > why does he need to know it? It only helps to ruin portability. Heh. At a guess, Arnaud is looking like he's in very early stages of learning Linux development. So, he's probably not exactly sure what he does or doesn't need to know, and is doing his best with the knowledge he has. :)

?Okay, I have found it, I must use "libc.so.6" and the function name is strdup not _strdup...

So, it push to an other questions : Is libc.so.6 present on any linux distro ? (I use a fedora 13 here)

On 10/19/2010 11:25 PM, arnaud.champion(a)devatom.fr wrote: > ?I have tried libc.so and it doesn't contains _strdup, amybe it's strdup > instead I will try. Anyway I have a little question (a windowsian > question :) ). Under windows I have a tool named "depends.exe" with it, > I can sse what is exposed thru a dll, is there any equivalent under linux > ? Hmmm, two tools might be useful, but I don't personally know them in much depth: + ldd + nm ldd can be used on an executable file, to show which dynamic libraries that file needs. For example, if I have the program "/bin/bash": $ ldd /bin/bash linux-vdso.so.1 => (0x00007fff999ff000) libtinfo.so.5 => /lib64/libtinfo.so.5 (0x00000030cd600000) libdl.so.2 => /lib64/libdl.so.2 (0x00000030bc200000) libc.so.6 => /lib64/libc.so.6 (0x00000030bba00000) /lib64/ld-linux-x86-64.so.2 (0x00000030bb600000) The "nm" program, can be used on a dynamic library to show which symbols it provides. For example, on /lib64/libc.so.6: $ nm /lib64/libc.so.6 <snip> 00000030bbd7ba60 B __daylight 00000030bba2c550 T __dcgettext 00000030bba2c550 t __dcgettext_internal 00000030bba2d5e0 t __dcigettext 00000030bba2dfc0 t __dcngettext 00000030bba7c600 T __default_morecore 00000030bba33140 t __default_sigpause 00000030bba2c560 T __dgettext 00000030bba95be0 t __difftime 00000030bbb1e7c0 t __dl_iterate_phdr 00000030bba2dfd0 t __dngettext 00000030bba4f150 t __dprintf <snip - it is a long list> Both nm and ldd can be given options, which change what they display. Looking at the questions you are asking, they are a bit unusual. There is nothing _wrong_ with your questions, but they make me curious what you are trying to do. If you are ok to explain the idea you are trying, we might know of a better or easier way. (no guarantees though!) :) Regards and best wishes, Justin Clift > Arnaud

On 10/19/2010 07:13 AM, arnaud.champion(a)devatom.fr wrote: > > ?Well, as I have said I work on .Net/Mono bindings. > > To make bindings, we use largely the marshaling methods of .Net/Mono. I > was working on bindings virConnectOpenAuth, so I have de marshal > virConnectCredential struct, these kind of thing. Matthias Bolte help me > a lot to make all the process thru callback working. And we have > discover that the virConnectCredential was reseted by the marshaling > process (in particular marshaling process free the result member of the > virConnectCredential, and in fact, for libvirt, it's the driver > responsability to free the result member). So Matthias suggest me to > bind strdup to .Net and use it to be sure that the result member is not > freed by marshaling. And it works. strdup() is nothing more than malloc() followed by strcpy(); it is such a fundamental operation to copy strings into newly allocated memory that I'm surprised that you don't know how to do that natively in C# without having to bind in strdup() in the first place (even if you do have to do it in two phases of allocation and copying rather than as a single function call).