--- file_not_specified_in_diff	
+++ file_not_specified_in_diff	
@@ -19,1 +19,2 @@ 
-"regen", "rsync",  "search",   "sync", "system", "unmerge", "world"
---
+"regen", "rsync",  "search",   "sync", "system", "unmerge", "world",
+"diff" #Add diff to list of actions
@@ -218,1 +219,1 @@ 
-if ("--pretend" in myopts) or (myaction=="search"):
---
+if ("--pretend" in myopts) or (myaction in ["search", "diff"] ): #Do not require root to see diffs
@@ -1652,0 +1653,85 @@ 
+#INSERTED
+#Prints a list of packages, showing differences in compile-time options to the settings that would be used if
+#recompiled now. If an argument is supplied, it only displays packages of which the argument is a substring.
+#The location of the vardbtree is hardcoded because it is in the vardbiapi.
+#TODO: allow regular expressions as search arguments.
+elif "diff"==myaction:
+	#If we were supplied with a search string
+	if ( myfiles ):
+		print "Scaning for packagenames including \"" + myfiles[0] + "\"."
+	else:
+		print "Scanning all packages." 
+	print
+	
+	#Set root for vardb
+	myRoot = portage.root + "var/db/pkg/"
+	#Get a list of the options currenty used to compile.
+	currCFlags = portage.settings["CFLAGS"].split( " " )
+		
+	#Scan through all categories
+	try:
+		categories = portage.listdir ( myRoot )
+	except OSError:
+		print "Error opening catalogue " + myRoot + "."
+		sys.exit(-1)
+	
+	categories.sort()
+	for y in categories:
+		#Scan through all packages, listing their flags
+		try:
+			pkgList = portage.listdir ( myRoot + y )
+		except OSError:
+			pkgList = [] #In case there is a file in the /var/db/pkg/
+		pkgList.sort()
+		for x in pkgList:
+			#Check if this file satisfies search criteria
+			#TODO: replace string.find by regular expression equiv. 
+			if ( not myfiles or string.find ( y + "/" + x, myfiles[0] ) >=0 ):
+				#Print name of package
+				print green("*") + y + "/" + x + ": "
+				#Get info about package
+				try:
+					myCFlagsFile = open ( myRoot + y + "/" + x + "/CFLAGS", "r" )
+				except (IOError,OSError): 
+					print red( "Error opening CFLAGS file" )
+					print
+					continue #Skip this package and go on to next one.
+					
+				#Read in file, stripping last char, which is a '\n'
+				myCFlagsData = string.rstrip ( myCFlagsFile.readline() ) 
+				#Split data into separate options
+				myCFlags = myCFlagsData.split( " " )
+				#Make a list of settings this package does not have
+				myCFlagsLacking = ""
+				for z in currCFlags:
+					if ( not z in myCFlags ):
+						myCFlagsLacking += ( z + " " )
+
+				#Make a list of settings this package has in excess
+				myCFlagsExtra = ""
+				for z in myCFlags:
+					if ( not z in currCFlags ):
+						myCFlagsExtra += ( z + " " )					
+
+				#If settings match
+				if ( not myCFlagsLacking and not myCFlagsExtra ):
+					print blue("Up to date")
+					
+				#If there are differences
+				else:
+					#Print options
+					print red("Lacks:  ") + myCFlagsLacking
+					print red("Excess: ") + myCFlagsExtra
+				#Done displaying this package
+				print 
+				#Close cflags file
+				myCFlagsFile.close()
+			#else:
+				#Package does not match criteria. Do not show.
+				#print y + "/" + x + " " + str( string.find( myfiles[0], y + "/" + x ) )
+			#End processing file. If no match then nothing done
+		#End scanning packages
+	#End scanning categories
+
+#/INSERTED
+