--- global~.c	2013-07-05 17:36:57 +1000
+++ global.c	2013-07-11 00:11:43 +1000
@@ -59,6 +59,7 @@
 static void help(void);
 static void setcom(int);
 int decide_tag_by_context(const char *, const char *, int);
+int prepend_args(const char *, int *, char ***);
 int main(int, char **);
 int completion_tags(const char *, const char *, const char *, int);
 void completion(const char *, const char *, const char *, int);
@@ -150,10 +151,11 @@
 static struct option const long_options[] = {
 	{"absolute", no_argument, NULL, 'a'},
 	{"completion", no_argument, NULL, 'c'},
-	{"color", no_argument, NULL, 'C'},
-	{"colour", no_argument, NULL, 'C'},
+	{"color", optional_argument, NULL, 'C'},
+	{"colour", optional_argument, NULL, 'C'},
 	{"definition", no_argument, NULL, 'd'},
 	{"regexp", required_argument, NULL, 'e'},
+	{"ext-regexp", no_argument, NULL, 'E'},
 	{"file", no_argument, NULL, 'f'},
 	{"local", no_argument, NULL, 'l'},
 	{"file-list", required_argument, NULL, 'L'},
@@ -162,6 +164,7 @@
 	{"basic-regexp", no_argument, NULL, 'G'},
 	{"ignore-case", no_argument, NULL, 'i'},
 	{"idutils", no_argument, NULL, 'I'},
+	{"match-case", no_argument, NULL, 'm'},
 	{"other", no_argument, NULL, 'o'},
 	{"only-other", no_argument, NULL, 'O'},
 	{"print-dbpath", no_argument, NULL, 'p'},
@@ -170,6 +173,7 @@
 	{"reference", no_argument, NULL, 'r'},
 	{"rootdir", no_argument, NULL, 'r'},
 	{"symbol", no_argument, NULL, 's'},
+	{"project", no_argument, NULL, 'S'},
 	{"tags", no_argument, NULL, 't'},
 	{"through", no_argument, NULL, 'T'},
 	{"update", no_argument, NULL, 'u'},
@@ -335,6 +339,56 @@
 	}
 	return db;
 }
+/**
+ * prepend_args: insert arguments from a string into an array
+ *
+ *	@param[in]	var   string containing arguments to be inserted
+ *	@param		argc  current and new array size
+ *	@param		argv  current and new array arguments
+ *	@return 	number of arguments prepended
+ *
+ *	@note preserves first element and assumes NULL exists after last.
+ *	@note backslash is used to escape the next character.
+ */
+int
+prepend_args(const char *var, int *argc, char ***argv)
+{
+	int cnt = 0;
+
+	if (var && *var) {
+		char *buf = check_strdup(var);
+		char *s = buf;
+		char *d = buf;
+		char **a, **args, **arg = *argv;
+		int i;
+		for (;;) {
+			while (*s && isspace(*s))
+				++s;
+			if (!*s)
+				break;
+			++cnt;
+			do {
+				*d = *s++;
+				if (*d == '\\' && *s)
+					*d = *s++;
+				++d;
+			} while (*s && !isspace(*s));
+			*d++ = '\0';
+		}
+		a = args = check_malloc((*argc + cnt + 1) * sizeof(char*));
+		*a++ = *arg++;
+		s = buf;
+		for (i = 0; i < cnt; ++i) {
+			*a++ = s;
+			s = strchr(s, '\0') + 1;
+		}
+		memcpy(a, arg, *argc * sizeof(char*));
+		*argc += cnt;
+		*argv = args;
+	}
+
+	return cnt;
+}
 int
 main(int argc, char **argv)
 {
@@ -343,8 +397,9 @@
 	int optchar;
 	int option_index = 0;
 
+	prepend_args(getenv("GLOBAL_OPTIONS"), &argc, &argv);
 	logging_arguments(argc, argv);
-	while ((optchar = getopt_long(argc, argv, "acCde:ifgGIlL:noOpPqrstTuvVx", long_options, &option_index)) != EOF) {
+	while ((optchar = getopt_long(argc, argv, "acCde:EifgGIlL:mnoOpPqrsStTuvVx", long_options, &option_index)) != EOF) {
 		switch (optchar) {
 		case 0:
 			break;
@@ -356,7 +411,17 @@
 			setcom(optchar);
 			break;
 		case 'C':
-			Cflag++;
+			if (optarg) {
+				if (!strcmp(optarg, "never"))
+					Cflag = 0;
+				else if (!strcmp(optarg, "always"))
+					Cflag = 1;
+				else if (!strcmp(optarg, "auto"))
+					Cflag = 2;
+				else
+					die_with_code(2, "unknown color type for the --color option.");
+			} else
+				Cflag = 2;
 			break;
 		case 'd':
 			dflag++;
@@ -364,6 +429,9 @@
 		case 'e':
 			av = optarg;
 			break;
+		case 'E':
+			Gflag = 0;
+			break;
 		case 'f':
 			fflag++;
 			xflag++;
@@ -389,6 +457,9 @@
 		case 'L':
 			file_list = optarg;
 			break;
+		case 'm':
+			iflag = 0;
+			break;
 		case 'n':
 			nflag++;
 			if (optarg) {
@@ -424,6 +495,9 @@
 		case 's':
 			sflag++;
 			break;
+		case 'S':
+			Tflag = 0;
+			break;
 		case 't':
 			tflag++;
 			break;
@@ -532,10 +606,6 @@
 			warning("cannot encode '/' and '.' in the path. Ignored.");
 		set_encode_chars((unsigned char *)encode_chars);
 	}
-	if (getenv("GTAGSTHROUGH"))
-		Tflag++;
-	if (getenv("GTAGSCOLOR"))
-		Cflag++;
 	if (qflag)
 		vflag = 0;
 	if (show_help)
@@ -547,6 +617,8 @@
 		else if (!(getenv("ANSICON") || LoadLibrary("ANSI32.dll")))
 			Cflag = 0;
 #endif
+		if (Cflag == 2 && !isatty(1))
+			Cflag = 0;
 		if (Cflag)
 			highlight_init();
 	}
--- manual~.in	2013-07-05 17:36:57 +1000
+++ manual.in	2013-07-11 00:37:58 +1000
@@ -25,12 +25,12 @@
 @HEADER	GLOBAL,1,May 2012,GNU Project
 @NAME	global - print locations of the specified object.
 @SYNOPSIS
-	@name{global} [-aCdGilnqrstTvx] [-e] @arg{pattern}
-	@name{global} -c[diIoOPrsT] @arg{prefix}
+	@name{global} [-aCdEGilmnqrsStTvx] [-e] @arg{pattern}
+	@name{global} -c[diImoOPrsST] @arg{prefix}
 	@name{global} -f[aCdlnqrstvx] [-L file-list] @arg{files}
-	@name{global} -g[aCGilnoOqtvVx] [-L file-list] [-e] @arg{pattern} address@hidden
-	@name{global} -I[aCilnqtvx] [-e] @arg{pattern}
-	@name{global} -P[aCGilnoOqtvVx] [-e] @arg{pattern}
+	@name{global} -g[aCEGilmnoOqtvVx] [-L file-list] [-e] @arg{pattern} address@hidden
+	@name{global} -I[aCilmnqtvx] [-e] @arg{pattern}
+	@name{global} -P[aCEGilmnoOqtvVx] [-e] @arg{pattern}
 	@name{global} -p[qrv]
 	@name{global} -u[qv]
 @DESCRIPTION
@@ -91,10 +91,11 @@
 	@begin_itemize
 	@address@hidden, @option{--absolute}}
 		Print absolute path name. By default, print relative path name.
-	@address@hidden, @option{--color}, @option{--colour}}
-		Use color to highlight the pattern within the line. The default
-		color is bold red text on current background; the environment
-		variable @var{GREP_COLORS} or @var{GREP_COLOR} defines it.
+	@address@hidden, @option{--color}, @option{--colour}} @arg{when}
+		Use color to highlight the pattern within the line; @arg{when} may be one
+		of: @arg{never}, @arg{always} or @arg{auto} (default). The default color is bold red
+		text on current background; the environment variable @var{GREP_COLORS} or
+		@var{GREP_COLOR} defines it.
 	@address@hidden, @option{--definition}}
 		Print locations of object definitions.
 	@address@hidden @arg{context}}
@@ -105,6 +106,9 @@
 		editors and IDEs.
 	@address@hidden, @option{--regexp} @arg{pattern}}
 		Use @arg{pattern} as the pattern; useful to protect patterns beginning with @file{-}.
+	@address@hidden, @option{--ext-regexp}}
+		Interpret @arg{pattern} as an extended regular expression.
+		This is provided to override @option{-G} in @var{GLOBAL_OPTIONS}.
 	@address@hidden @arg{chars}}
 		Convert path characters in @arg{chars} into a '%' symbol, followed by the
 		two-digit hexadecimal representation of the character.
@@ -121,6 +125,9 @@
 	@address@hidden
 		Execute literal search instead of regular expression search.
 		This option is only valid when the @option{-g} command is specified.
+	@address@hidden, @option{--match-case}}
+		Consider case distinctions in the pattern.
+		This is provided to override @option{-i} in @var{GLOBAL_OPTIONS}.
 	@address@hidden @arg{part}}}
 		Specify the matched part of path name.
 		This option is valid only with the @option{-c} command with the @option{-P} option.
@@ -153,6 +160,9 @@
 		The @option{--result=ctags} and @option{--result=ctags-x} options are
 		equivalent to the @option{-t} and @option{-x} options respectively.
 		The @option{--result} option is given more priority than the @option{-t} and @option{-x} options.
+	@address@hidden, @option{--project}}
+		Consider only the project's tag files.
+		This is provided to override @option{-T} in @var{GLOBAL_OPTIONS}.
 	@address@hidden @arg{file}}
 		Update tag files using @xref{gtags,1} with @option{--single-update} option.
 		It is considered that @arg{file} was added or updated,
@@ -242,12 +252,12 @@
 	@address@hidden
 		If this variable is set, @file{$MAKEOBJDIRPREFIX} is used as the prefix
 		of BSD-style objdir. The default is @file{/usr/obj}.
-	@address@hidden
-		If this variable is set, the @option{-T} option is specified.
 	@address@hidden
 		If this variable is set, the @option{--encode-path=" <TAB>"} option is specified.
-	@address@hidden
-		If this variable is set, the @option{-C} option is specified.
+	@address@hidden
+		Use this variable to always add options to the beginning of the
+		command line (like 'global $GLOBAL_OPTIONS ...').
+		Backslash is used to escape the next character.
 	@address@hidden
 		The color to use for @option{-C}; @var{GREP_COLORS} has precedence.
 	@address@hidden