Re: ls-mntd-fs.m4 fails to detect how to read list of mounted filesystems on Minix

[Jim Meyering]

Richard Yao wrote:

> On 07/28/2012 02:13 AM, Richard Yao wrote:
>> I used the following ISO to install Minix in KVM:
>>
>> http://www.minix3.org/iso/minix3_2_1_ide_20120622_f8c6b27.iso.bz2
>>
>> coreutils 8.16 and findutils 4.2.33 both fail to build on Minix with the
>> following configure error:
>>
>> checking for next_dev... no
>> checking for fs_stat_dev... no
>> checking fs_info.h usability... no
>> checking fs_info.h presence... no
>> checking for fs_info.h... no
>> checking for BEOS mounted file system support functions... no
>> checking whether it is possible to resort to fread on /etc/mnttab... no
>> configure: error: could not determine how to read list of mounted file
>> systems
>>
>> Unfortunately, I am not familiar with what is failing. I have attached
>> the config.log from coreutils 8.16.
>
> Minix has /etc/mtab:
>
> -bash-4.2$ cat /etc/mtab
> /dev/c0d0p0s0 / 3 rw
> /dev/c0d0p0s2 /usr MFSv3 rw
> /dev/c0d0p0s1 /home MFSv3 rw
> none /sys devman rw
>
> It looks like the check for it expects /usr/include/mnttab.h to exist,
> which causes it to fail.

Thanks for the report.

That is because gnulib's mounted file system module has never been taught
how to deal with Minix 3: its getmntinfo signature is different from the
others, and hence is not detected, and the regular fallback of using
fread fails because other systems that would fall back to using fread
all had /etc/mnttab (with entries described in <mnttab.h>), while Minix 3
lacks both the /etc file and that header.

To remedy that, m4/ls-mntd-fs.m4 and lib/mountlist.c will probably
have to test-for/use (resp.) Minix 3's getmntinfo function:

    http://www.minix3.org/manpages/html3/getmntinfo.html

    int getmntinfo(struct statvfs **mntbufp, int flags)

If someone with an existing minix 3 environment wants to work on it,
that'd be great.  Otherwise, I will propose a patch.