"To compile a custom kernel for the same release as you already have
installed you only need the kernel syssrc.tgz file."

Ok : extract syssrc.tgz like is said in :
http://netbsd.org/Documentation/kernel/#downloading_kernel_source

"Unless you are updating NetBSD 1.6, build the new kernel via the
command cd /usr/src && ./build.sh kernel=MYCONF"

But there is no build.sh in /usr/src.

What I am missing ?

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