#line feature in C preprocessor

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I'm writing some programs using Berkeley Ingres and the EQUEL
preprocessor.  Now this EQUEL was written for version 6, and suffers
from some problems.  For instance, it doesn't insert the #line
directives, so error messages from the C compiler invariably refer to
the wrong line.  I didn't have time to fix EQUEL, so I inserted in each
of my ".q" files the line:

	#line 2 "<filename>.q"

at the beginning of the file.  My trouble is that these files all have
some #include lines following them, and the C preprocessor resets the
file name back to filename.c after an include file is processed!  I
have circumvented the problem once again by placing my #line directive
following all #includes, but what I would like is:

1)	To know if this filename-resetting is a bug or a feature.  By
	the way, has anybody ever produced documentation on the
	preprocessor?  I would greatly appreciate a copy.  Just out of
	curiosity, is the __FILE__ feature described anywhere on vanilla
	Unix other than in /usr/include/assert.h?

2)	If this is a bug, does anybody have the fixes?

3)      Best of all, does anybody have a version of EQUEL that has been
	modified to use the #line directive?  We're running VAXen here,
	so versions that understand their word sizes are preferred, but
	I'll take the source code for a version that works on an 11 if
	it's available.

				Thanks in advance,
					-- Steve Wartik
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