This library provides an interpreter for CGM '86 binary encoded
Computer Grapics Metafiles. It will draw the first picture in a
specified file into a Pixmap and return that Pixmap.

Files:

cgm.h contains common definitions (types, etc.) for all of the cgm
processing modules. Not needed by external programs.

spec.h contains the sepcification for the external entry point:

Pixmap CGMFileToPixmap (Screen        	*screen,
			char	        *filename,
			int		depth,
			Colormap	colormap,
			Visual		*visual,
			GC	        gc,
			Dimension     	*ret_width,
			Dimension     	*ret_height,
			Pixel         	**ret_colors,
			int	        *ret_number);

filename gives the name of the cgm file to be opened. It is not
munged in any manner. The first picture in the file will be written
into a Pixmap of dimension *ret_width by *ret_height. These are not
read on input, and presently will always fit within a 512 square
unless the cgm file explicitly asks for a different size by setting
the scaling mode to be metric. The Pixmap is the return value.

screen, depth and visual are used only on input as information on the
display to be used. gc is used to provide default foreground and
background colors, but these may be overridden by the cgm file. It is
not altered.

If colors are added to the colormap (by XAllocColor), their number and
Pixels will be in *ret_number and *ret_colors.

cgmcmds.c is the basic command module. It both interprets each cgm
command and invokes the XLib routines to perform the operations
requested, so it uses some XLib specific operations. I.e., XLib type
storage is used for the data.

cgmcommon.c has routines which are encoding and device independent,
i.e., not very many.

cgmio.c has the I/O routines for reading in the cgm file.

cgmtext.c has the text handling routines, including the definition of
a single stroked font.

getcgm.c has the external entry point, and interfaces it to the guts
of the interpreter, i.e., it has the outermost "do-loop".

testcgm.c is not part of the interpreter proper, but simply a test
program to grab a cgm file (either "test.cgm", or argv[1]), open a
window and copy the resulting Pixmap into it. It does no backing
store. 

Error messages: all error messages are of the form, e.g., 
"burp(stderr, "warning, %d\n", some_int);"
where "burp" is defined to be "fprintf" in cgm.h. If wanted, burp can
be redefined.