Example: Starting Hello

The easiest way to start an L4 application using the L4 loader is to pass the name of the executable as command line argument to the loader. The example below assumes GRUB loads files via the network. Loader uses the BMODFS file provider, a simple RAM-based application, to access files:

 # menu.lst

 set ND       = "(nd)/tftpboot/drops"
 set BIN_PATH = "$(ND)/bin"

 title Hello World
 kernel $(BIN_PATH)/bootstrap
 modaddr 0x02000000
 module $(BIN_PATH)/fiasco -nokdb -serial -serial_esc
 module $(BIN_PATH)/l4v2/sigma0
 module $(BIN_PATH)/l4v2/roottask task modname "bmodfs" attached 1 modules
 module $(BIN_PATH)/l4v2/names
 module $(BIN_PATH)/l4v2/log
 module $(BIN_PATH)/l4v2/dm_phys
 module $(BIN_PATH)/l4v2/simple_ts
 module $(BIN_PATH)/l4v2/bmodfs
	 module $(BIN_PATH)/l4v2/hello
 module $(BIN_PATH)/l4v2/loader --fprov=BMODFS hello

Note:

The default file provider the loader communicates with is tftp. This server accepts filenames in the GRUB syntax and loads files through the network using the TFTP protocol. Therefore, you must prepend "(nd)/". The binary must be accessible by the TFTP protocol (e.g. the binaries must be world-readable). The above example using TFTP looks like this:

 # menu.lst

 set ND       = "(nd)/tftpboot/drops"
 set BIN_PATH = "$(ND)/bin"

 title Hello World
 kernel $(BIN_PATH)/bootstrap
 modaddr 0x02000000
 module $(BIN_PATH)/fiasco -nokdb -serial -serial_esc
 module $(BIN_PATH)/l4v2/sigma0
 module $(BIN_PATH)/l4v2/roottask
 module $(BIN_PATH)/l4v2/names
 module $(BIN_PATH)/l4v2/log
 module $(BIN_PATH)/l4v2/dm_phys
 module $(BIN_PATH)/l4v2/simple_ts
 module $(BIN_PATH)/l4v2/l4io
 module $(BIN_PATH)/l4v2/ore
 module $(BIN_PATH)/l4v2/tftp --server=192.168.0.2
 module $(BIN_PATH)/l4v2/loader $(BIN_PATH)/l4v2/hello