In a script under freebsd I issued the following tar command 
successfully while under netbsd it fails saying

uffBSD# /bin/tar -cz 
/etc > /pgdump/etc.5.tar.gz
tar: Failed open to write on /dev/nrst0 
(Device not configured)
tar: Unexpected EOF on archive file

I tried 
(under netbsd) the following but:

uffBSD# /bin/tar -cz /pgdump/etc.5.
tar.gz /etc
tar: Failed open to write on /dev/nrst0 (Device not 
configured)
tar: Unexpected EOF on archive file

Besides issuing

uffBSD# /bin/tar -cfz /pgdump/etc.5.tar.gz /etc/*
tar: Removing leading 
/ from absolute path names in the archive

But there's NOTHING inside 
etc.t.tar.gz.

Could you please help me?

Vittorio