Re: dynamic-link on libc

[Jeff Mickey <j@codemac.net>]

That solves my problem! Thank you so much :)

libc is a special case, and I should have thought about it more.

  //  mickey

On Fri, Aug 4, 2017, at 14:44, Matt Wette wrote:
> 
> > On Aug 4, 2017, at 2:15 PM, Jeff Mickey <j@codemac.net> wrote:
> > 
> > Hi guilers!
> > 
> > I cannot seem to call `dynamic-link' on libc.
> > 
> > I'm trying to write a simple, dumb wrapper around syslog using the (system foreign) dynamic library to learn how to use the dynamic ffi.
> > 
> > (use-modules (system foreign))
> > (define libcsyslog (dynamic-link "libc"))  (define syslog  (let ((f (pointer->procedure 	    void (dynamic-func "syslog" libcsyslog) (list int 	    '*))))    (lambda (level msg)      (let* ((clevel level) 	     (cmsg (string->pointer msg))) (f clevel cmsg))))) 	(syslog 3 "hello there") 
> > 
> > This works when I symlink /lib/x86_64-linux-gnu/libc.so.6 to libc.so, but it looks like the libtool library that is doing the load doesn't accept names that end in ".6" as a library name, and when I used the full path it just says "file not found".
> > 
> > Anyone have suggestions? I looked at the dynl.c sysdep_dynl_link function, but I'm not sure I understand libtool well enough to know what lt_dlopenext should be doing.
> > 
> > I should add I tested this on a debian system with a debian provided guile, and a "user installed guix" guile install as well.
> > 
> > Thanks!
> > 
> > //  codemac
> > 
> 
> I don’t think you need to dynamic-link libc; just use (dynamic-func
> "syslog" (dynamic-link)).
>