/usr/share/live/build/bootloaders/pxelinux/ is in open-infrastructure-system-build 20161101-lts2-2.
This file is owned by root:root, with mode 0o755.
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/usr/share/live/build/bootloaders/pxelinux/advanced.cfg
/usr/share/live/build/bootloaders/pxelinux/hdt.c32
/usr/share/live/build/bootloaders/pxelinux/install.cfg
/usr/share/live/build/bootloaders/pxelinux/ldlinux.c32
/usr/share/live/build/bootloaders/pxelinux/libcom32.c32
/usr/share/live/build/bootloaders/pxelinux/libgpl.c32
/usr/share/live/build/bootloaders/pxelinux/libmenu.c32
/usr/share/live/build/bootloaders/pxelinux/libutil.c32
/usr/share/live/build/bootloaders/pxelinux/live.cfg.in
/usr/share/live/build/bootloaders/pxelinux/menu.cfg
/usr/share/live/build/bootloaders/pxelinux/pxelinux.0
/usr/share/live/build/bootloaders/pxelinux/pxelinux.cfg/
/usr/share/live/build/bootloaders/pxelinux/pxelinux.cfg/default
/usr/share/live/build/bootloaders/pxelinux/splash.svg
/usr/share/live/build/bootloaders/pxelinux/stdmenu.cfg
/usr/share/live/build/bootloaders/pxelinux/vesamenu.c32