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<lloda>e^x: It seems so. Please send a message to bug-guile@gnu.org.

<Labu>Hello !

<roelj>Is it possible to get a FILE* from a Guile port, so that it can be passed to a foreign function?

<amz3>roelj: if you are looking for the file descriptor associated with a port, there is 'fileno' procedure

<amz3>or 'port->fdes'

<roelj>And that returns a number, not a pointer. How do I go from file descriptor to a FILE*?

<amz3>I think FILE is a number actually

<amz3>I need to check

<roelj>So (scm->pointer ...) should do the trick?

<amz3>oops sorry

<amz3>loooking at 'man fdopen' it seems like fd and FILE are different things

<roelj>Yeah, I just realized this too. So, I can pass the file descriptor, and then I'll have to do fdopen on it to get a FILE*

<amz3>maybe you can 'fdopen' the fd returned by guile, idk, maybe some else knows better

<amz3>yes maybe

<roelj>Well, thanks. I'm going to give this a try.

<amz3>roelj: btw, you don't need 'scm->pointer' an integer, if the C function expect an int, you can pass the scheme number directly to ffi procedure it will be handled correctly

<roelj>Well, it expects a FILE*, not an int :-)

<roelj>Uhh.. how do I use the 'fdopen' C-function? Can I just dynamic-link glibc?

<amz3>yes

<civodul>roelj: there's an 'fdopen' procedure in Guile

<roelj>civodul: But it returns a port, not a FILE*, right?

<civodul>right, FILE* are libc-only things

<civodul>yeah i guess i misunderstood what you were looking for :-)

<roelj>That's alright :). So I wrote a C function that takes a file descriptor, then does: FILE* file = fdopen (fd, "rw"); return file;

<roelj>Then I loaded it with dynamic-func, but when calling it, it doesn't actually write to the file.

<roelj>And the C function calling fprintf (file, ...) returns -1 --> So something went wrong.

<roelj>Any ideas what might go wrong?

<roelj>Because I am out of clues

<amz3>strace might give more clues

<roelj>Ha! good idea

<civodul>roelj: do you really need FILE*?

<civodul>because then you have to use exclusively FILE* functions

<civodul>and FILE* does caching, so writing to a FILE* doesn't take effect immediately

<roelj>civodul: Yes, I'm trying to write an interface to a C library. And there's this one function that takes a FILE* to do all of the printing..

<roelj>Too bad. Even when using fopen from glibc, the fprintf eventually fails. :(

<roelj>Well, it was a fun experiment.

<bavier`>amz3, OrangeShark: is it possible to do a shallow clone with guile-git?

<bavier`>amz3, OrangeShark: nvm, I couldn't find anything in the texi documentation, but found the procedures in the modules

<OrangeShark>bavier`: I don't believe libgit2 supports shallow clones

<bavier`>OrangeShark: ah, indeed. there are a few open bugs/issues/feature requests

<bavier`>hmm, this makes things more difficult

IRC channel logs

2018-02-07.log