pkg_add: Warning: package `digest-20160304' was built for a platform:
pkg_add: NetBSD/x86_64 8.99.8 (pkg) vs. NetBSD/x86_64 8.99.9 (this host)
pkg_add: Warning: package `cwrappers-20171108' was built for a platform:
pkg_add: NetBSD/x86_64 8.99.8 (pkg) vs. NetBSD/x86_64 8.99.9 (this host)
pkg_add: Warning: package `checkperms-1.11nb1' was built for a platform:
pkg_add: NetBSD/x86_64 8.99.8 (pkg) vs. NetBSD/x86_64 8.99.9 (this host)
pkg_add: Warning: package `suse32_base-13.1nb14' was built for a platform:
pkg_add: NetBSD/x86_64 8.99.8 (pkg) vs. NetBSD/x86_64 8.99.9 (this host)
suse32_base-13.1nb14: rebuilding run-time library search paths database
suse32_base-13.1nb14: populating /usr/pkg/emul/linux32/dev
pkg_add: Warning: package `suse32_x11-13.1nb7' was built for a platform:
pkg_add: NetBSD/x86_64 8.99.8 (pkg) vs. NetBSD/x86_64 8.99.9 (this host)
suse32_x11-13.1nb7: rebuilding run-time library search paths database
===========================================================================
$NetBSD: MESSAGE.NetBSD,v 1.1 2013/12/05 11:42:14 obache Exp $

Do not forget to include COMPAT_LINUX in your kernel configuration file.
Linux binaries require this option in order to work.

Most Linux binaries also require procfs to be mounted with -o linux.
This can be automated by adding the following to your /etc/fstab:

procfs /emul/linux32/proc procfs ro,linux

Some Linux binaries also require tmpfs to be mounted on /dev/shm.
This can be automated by adding the following to your /etc/fstab:

tmpfs /emul/linux32/dev/shm tmpfs rw,-m1777

===========================================================================