Re: [RFC PATCH] samples: fix building fs-monitor on musl systems.

From: Jan Kara
Date: Mon Jun 30 2025 - 07:06:40 EST


On Mon 30-06-25 16:00:11, Brahmajit Das wrote:
> On musl systems with make allyesconfig fs-monitor.c fails to build with
>
> samples/fanotify/fs-monitor.c:22:9: error: unknown type name '__s32'
> 22 | __s32 error;
> | ^~~~~
> samples/fanotify/fs-monitor.c:23:9: error: unknown type name '__u32'
> 23 | __u32 error_count;
> | ^~~~~
> samples/fanotify/fs-monitor.c: In function 'handle_notifications':
> samples/fanotify/fs-monitor.c:98:50: error: 'fsid_t' has no member named 'val'; did you mean '__val'?
> 98 | fid->fsid.val[0], fid->fsid.val[1]);
> | ^~~
> | __val
> samples/fanotify/fs-monitor.c:98:68: error: 'fsid_t' has no member named 'val'; did you mean '__val'?
> 98 | fid->fsid.val[0], fid->fsid.val[1]);
> | ^~~
> | __val
>
> This is due to sys/fanotify.h on musl does not include
> linux/fanotify.h[0] unlike glibc which includes it. This also results in
> fsid not being of type __kernel_fsid_t, rather the libc's definition of
> it which does not have val, but instead __val.
>
> [0]: https://git.musl-libc.org/cgit/musl/tree/include/sys/fanotify.h
> Signed-off-by: Brahmajit Das <listout@xxxxxxxxxxx>

Thanks! Added to my tree.

Honza

> ---
> samples/fanotify/fs-monitor.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/samples/fanotify/fs-monitor.c b/samples/fanotify/fs-monitor.c
> index 608db24c471e..28c0a652ffeb 100644
> --- a/samples/fanotify/fs-monitor.c
> +++ b/samples/fanotify/fs-monitor.c
> @@ -12,6 +12,9 @@
> #include <sys/fanotify.h>
> #include <sys/types.h>
> #include <unistd.h>
> +#ifndef __GLIBC__
> +#include <asm-generic/int-ll64.h>
> +#endif
>
> #ifndef FAN_FS_ERROR
> #define FAN_FS_ERROR 0x00008000
> @@ -95,7 +98,11 @@ static void handle_notifications(char *buffer, int len)
> fid = (struct fanotify_event_info_fid *) info;
>
> printf("\tfsid: %x%x\n",
> +#if defined(__GLIBC__)
> fid->fsid.val[0], fid->fsid.val[1]);
> +#else
> + fid->fsid.__val[0], fid->fsid.__val[1]);
> +#endif
> print_fh((struct file_handle *) &fid->handle);
> break;
>
> --
> 2.50.0
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR