+# The syntax of this magic string is given in src/gras/DataDesc/ddt_convert.c
+# It kinda matches the values that the gras_arch_desc_t structure can take
+
+# Basically, the syntax is one char l or B for endianness (little or Big)
+# then there is a bunch of blocks separated by _.
+# C block is for char, I block for integers, P block for pointers and
+# D block for floating points
+# For each block there is an amount of chuncks separated by :, each of
+# them describing a data size. For example there is only one chunk
+# in the char block, because no architecture provide several sizes
+# of chars. In integer block, there is 4 chunks: "short int", "int",
+# "long int", "long long int". There is 2 pointer chunks for data
+# pointers and pointers on functions (thanks to the AMD64 madness).
+# Thee two floating points chuncks are for "float" and "double".
+# Each chunk is of the form datasize/minimal_alignment_size
+
+# These informations are used to convert a data stream from one
+# formalism to another. Only the GRAS_ARCH is transfered in the
+# stream, and it it of cruxial importance to keep these detection
+# information here synchronized with the data hardcoded in the
+# source in src/gras/DataDesc/ddt_convert.c
+
+# If you add something here (like a previously unknown architecture),
+# please add it to the source code too.
+# Please do not modify stuff here since it'd break the GRAS protocol.
+# If you really need to change stuff, please also bump
+# GRAS_PROTOCOL_VERSION in src/gras/Msg/msg_interface.h
+