what does menu.c32 does?
 

What does the following command of pxelinux config does:

default menu.c32

here menu.c32 is some binary file. what is it?

OK, menu.c32 is part of the com32 stuff in syslinux
( http://syslinux.zytor.com/wiki/index.php/SYSLINUX )
more specifically, it is a kernel that can display a semi-graphical
boot menu, and vesamenu.c32 can show a full color graphical menu(slax, etc)
( http://syslinux.zytor.com/wiki/index...mboot/menu.c32 )
download syslinux here, with menu.c32, etc
( http://www.kernel.org/pub/linux/utils/boot/syslinux/ )

now, if you wanna see usage of menu.c32 download my iso-usb-kit(which needs to be updated:(
( http://multidistro.com/downloads/odd...odds&ends.html )
and info on that here
( http://multidistro.com/downloads/odds&ends/readme.txt )

also, most of my downloads utilize menu.c32, as using vesamenu.c32 on usb
I always get a "password" request at boot and a white screen?!
don't know why...
( http://multidistro.com/downloads/downloads.html )

so, you got hdt.c32 (hardware detect tool), reboot.c32(reboots you), menu.c32/vesamenu.c32, and others
so, check it out

If menu.c32 is a kernel, then how it knows what menu items are described in config file? Does it read config file over TFTP second time after pxelinux does?