well there are several examples of this in the arch/um/drivers area. <blah>_user.c and <blah>_kern.c break out the userspace and kernel space parts of UML's dual personality.
Olivier Crameri wrote: > Well, yes, I could use this. > > But what I'm actually trying to understand is how to properly execute > regular C within the UML kernel to access the host OS. > > Thks, > > Olivier > > On 5 avr. 06, at 19:18, D. Bahi wrote: > >> what about this? >> >> http://user-mode-linux.sourceforge.net/iomem.html >> >> Olivier Crameri wrote: >>> Hi, >>> >>> I'm currently working on a project in which we are using UML to access >>> the host os and perform some operations. >>> More precisely, we would like to have a system call in UML that parses >>> a file in the host os. >>> >>> Since the UML kernel is a host process, I naively thought that I could >>> use regular C directly. Indeed, I was able to create my system call, >>> and then have some other C files compiled using host os headers such >>> as <stdio.h> and <stdlib.h> by putting them in the USER_OBJS list of >>> the Makefile. >>> >>> Unfortunately, I'm having some weird issues that I can't really >>> understand. I can read the file using fread, but only in a buffer that >>> I allocated using um_kmalloc. If I use a buffer allocated by malloc, >>> the fread fails. Then, even if I replace all my mallocs by >>> um_kmallocs, some libc functions (such as sscanf) don't seem to work >>> properly. I guess I'm missing something, but I can't figure out what. >>> >>> If anyone of you can help me, I'd really appreciate, >>> >>> With best regards, >>> >>> Olivier >>> >>> P.S.: I'm using 2.6.15.6 with the latest 2.6.15 patch and the guest >>> kernel runs in skas3 mode. >>> >>> >>> ------------------------------------------------------- >>> This SF.Net email is sponsored by xPML, a groundbreaking scripting >>> language >>> that extends applications into web and mobile media. Attend the live >>> webcast >>> and join the prime developer group breaking into this new coding >>> territory! >>> http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 >>> >>> _______________________________________________ >>> User-mode-linux-devel mailing list >>> User-mode-linux-devel@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel >> > > > > > ------------------------------------------------------- > This SF.Net email is sponsored by xPML, a groundbreaking scripting > language > that extends applications into web and mobile media. Attend the live > webcast > and join the prime developer group breaking into this new coding > territory! > http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 > _______________________________________________ > User-mode-linux-devel mailing list > User-mode-linux-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel
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