diff --git a/Makefile.in b/Makefile.in
index 5ae970a26..fb21fdf70 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -70,6 +70,8 @@ LIBTOOL_DEPS = @LIBTOOL_DEPS@
 
 SHELL = @SHELL@
 
+EGREP = @EGREP@
+GREP = @GREP@
 SED = @SED@
 
 INSTALL = $(SHELL) $(scriptdir)/install-sh -c
@@ -117,7 +119,7 @@ check check-verbose check-fuzzer fuzz pre-install: config.status
 	done
 
 uncrustify.files: Makefile
-	grep '\.[ch]$$' $(top_srcdir)/MANIFEST | grep -E -v '(/zlib/|/(arc4random|arc4random_uniform|chacha_private|charclass|fnmatch|getaddrinfo|getcwd|getdate|getentropy|getopt|getopt_long|glob|gram|inet_ntop|inet_pton|log_server.pb-c|mktemp|pw_dup|reallocarray|mktemp_test|protobuf-c|snprintf|stdbool|strlcat|strlcpy|sudo_queue|toke)\.[ch]$$)'  > uncrustify.files
+	$(GREP) '\.[ch]$$' $(top_srcdir)/MANIFEST | $(EGREP) -v '(/zlib/|/(arc4random|arc4random_uniform|chacha_private|charclass|fnmatch|getaddrinfo|getcwd|getdate|getentropy|getopt|getopt_long|glob|gram|inet_ntop|inet_pton|log_server.pb-c|mktemp|pw_dup|reallocarray|mktemp_test|protobuf-c|snprintf|stdbool|strlcat|strlcpy|sudo_queue|toke)\.[ch]$$)'  > uncrustify.files
 
 reformat: uncrustify.files
 	( cd $(top_srcdir) && uncrustify -c etc/uncrustify.cfg --replace --no-backup -F $(top_builddir)/uncrustify.files )
@@ -126,7 +128,7 @@ check-format: uncrustify.files
 	( cd $(top_srcdir) && uncrustify -c etc/uncrustify.cfg --check -F $(top_builddir)/uncrustify.files )
 
 spell:
-	( cd $(top_srcdir) && codespell -I etc/codespell.ignore -x etc/codespell.exclude `grep -E -v -f etc/codespell.skip MANIFEST` )
+	( cd $(top_srcdir) && codespell -I etc/codespell.ignore -x etc/codespell.exclude `$(EGREP) -v -f etc/codespell.skip MANIFEST` )
 
 cppcheck: config.status
 	rval=0; \
diff --git a/lib/eventlog/Makefile.in b/lib/eventlog/Makefile.in
index 84f8a5441..45b9ad2e9 100644
--- a/lib/eventlog/Makefile.in
+++ b/lib/eventlog/Makefile.in
@@ -33,6 +33,7 @@ incdir = $(top_srcdir)/include
 # Compiler & tools to use
 CC = @CC@
 LIBTOOL = @LIBTOOL@
+GREP = @GREP@
 
 # C preprocessor flags
 CPPFLAGS = -I$(incdir) -I$(top_builddir) -I$(srcdir) -I$(top_srcdir) @CPPFLAGS@
@@ -151,7 +152,7 @@ check-fuzzer:
 
 check: $(TEST_PROGS) check-fuzzer
 	@if test X"$(cross_compiling)" != X"yes"; then \
-	    if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	    if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 		LC_ALL=C.UTF-8; export LC_ALL; \
 	    else \
 		LC_ALL=C; export LC_ALL; \
diff --git a/lib/iolog/Makefile.in b/lib/iolog/Makefile.in
index 19ca7f3d4..2dde029d0 100644
--- a/lib/iolog/Makefile.in
+++ b/lib/iolog/Makefile.in
@@ -35,6 +35,7 @@ cross_compiling = @CROSS_COMPILING@
 CC = @CC@
 LIBTOOL = @LIBTOOL@
 SHA1SUM = @SHA1SUM@
+GREP = @GREP@
 SED = @SED@
 
 # Libraries
@@ -199,7 +200,7 @@ fuzz_iolog_json_seed_corpus.zip:
 	rm -rf $$tdir
 
 run-fuzz_iolog_json: fuzz_iolog_json
-	if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 	    LC_ALL=C.UTF-8; export LC_ALL; \
 	else \
 	    LC_ALL=C; export LC_ALL; \
@@ -226,7 +227,7 @@ fuzz_iolog_legacy_seed_corpus.zip:
 	rm -rf $$tdir
 
 run-fuzz_iolog_legacy: fuzz_iolog_legacy
-	if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 	    LC_ALL=C.UTF-8; export LC_ALL; \
 	else \
 	    LC_ALL=C; export LC_ALL; \
@@ -253,7 +254,7 @@ fuzz_iolog_timing_seed_corpus.zip:
 	rm -rf $$tdir
 
 run-fuzz_iolog_timing: fuzz_iolog_timing
-	if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 	    LC_ALL=C.UTF-8; export LC_ALL; \
 	else \
 	    LC_ALL=C; export LC_ALL; \
@@ -307,7 +308,7 @@ fuzz: run-fuzz_iolog_json run-fuzz_iolog_legacy run-fuzz_iolog_timing
 
 check-fuzzer: $(FUZZ_PROGS)
 	@if test X"$(cross_compiling)" != X"yes"; then \
-	    if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	    if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 		LC_ALL=C.UTF-8; export LC_ALL; \
 	    else \
 		LC_ALL=C; export LC_ALL; \
@@ -326,7 +327,7 @@ check-fuzzer: $(FUZZ_PROGS)
 
 check: $(TEST_PROGS) check-fuzzer
 	@if test X"$(cross_compiling)" != X"yes"; then \
-	    if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	    if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 		LC_ALL=C.UTF-8; export LC_ALL; \
 	    else \
 		LC_ALL=C; export LC_ALL; \
diff --git a/lib/util/Makefile.in b/lib/util/Makefile.in
index 67177febd..ff24c7b96 100644
--- a/lib/util/Makefile.in
+++ b/lib/util/Makefile.in
@@ -55,6 +55,7 @@ CPP = @CPP@
 HOSTCPP = @CPP_FOR_BUILD@
 LIBTOOL = @LIBTOOL@
 SHA1SUM = @SHA1SUM@
+GREP = @GREP@
 SED = @SED@
 AWK = @AWK@
 
@@ -331,7 +332,7 @@ fuzz_sudo_conf_seed_corpus.zip:
 	rm -rf $$tdir
 
 run-fuzz_sudo_conf: fuzz_sudo_conf
-	if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 	    LC_ALL=C.UTF-8; export LC_ALL; \
 	else \
 	    LC_ALL=C; export LC_ALL; \
@@ -397,7 +398,7 @@ fuzz: run-fuzz_sudo_conf
 
 check-fuzzer: $(FUZZ_PROGS)
 	@if test X"$(cross_compiling)" != X"yes"; then \
-	    if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	    if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 		LC_ALL=C.UTF-8; export LC_ALL; \
 	    else \
 		LC_ALL=C; export LC_ALL; \
@@ -413,7 +414,7 @@ check-fuzzer: $(FUZZ_PROGS)
 # Note: some regress checks are run from srcdir for consistent error messages
 check: $(TEST_PROGS) check-fuzzer
 	@if test X"$(cross_compiling)" != X"yes"; then \
-	    if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	    if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 		LC_ALL=C.UTF-8; export LC_ALL; \
 	    else \
 		LC_ALL=C; export LC_ALL; \
@@ -438,9 +439,9 @@ check: $(TEST_PROGS) check-fuzzer
 	    if test -f globtest; then \
 		mkdir -p `$(SED) 's@/[^/]*$$@@' $(srcdir)/regress/glob/files | sort -u`; \
 		touch `cat $(srcdir)/regress/glob/files`; \
-		chmod 0755 `grep '/r[^/]*$$' $(srcdir)/regress/glob/files`; \
-		chmod 0444 `grep '/s[^/]*$$' $(srcdir)/regress/glob/files`; \
-		chmod 0711 `grep '/t[^/]*$$' $(srcdir)/regress/glob/files`; \
+		chmod 0755 `$(GREP) '/r[^/]*$$' $(srcdir)/regress/glob/files`; \
+		chmod 0444 `$(GREP) '/s[^/]*$$' $(srcdir)/regress/glob/files`; \
+		chmod 0711 `$(GREP) '/t[^/]*$$' $(srcdir)/regress/glob/files`; \
 		./globtest $(srcdir)/regress/glob/globtest.in || rval=`expr $$rval + $$?`; \
 		rm -rf fake; \
 	    fi; \
diff --git a/logsrvd/Makefile.in b/logsrvd/Makefile.in
index fba163ace..c9ba8658c 100644
--- a/logsrvd/Makefile.in
+++ b/logsrvd/Makefile.in
@@ -36,6 +36,7 @@ cross_compiling = @CROSS_COMPILING@
 CC = @CC@
 LIBTOOL = @LIBTOOL@
 SHA1SUM = @SHA1SUM@
+GREP = @GREP@
 SED = @SED@
 
 # Our install program supports extra flags...
@@ -194,7 +195,7 @@ fuzz_logsrvd_conf_seed_corpus.zip:
 	rm -rf $$tdir
 
 run-fuzz_logsrvd_conf: fuzz_logsrvd_conf
-	if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 	    LC_ALL=C.UTF-8; export LC_ALL; \
 	else \
 	    LC_ALL=C; export LC_ALL; \
@@ -257,7 +258,7 @@ fuzz: run-fuzz_logsrvd_conf
 
 check-fuzzer: $(FUZZ_PROGS)
 	@if test X"$(cross_compiling)" != X"yes"; then \
-	    if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	    if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 		LC_ALL=C.UTF-8; export LC_ALL; \
 	    else \
 		LC_ALL=C; export LC_ALL; \
@@ -272,7 +273,7 @@ check-fuzzer: $(FUZZ_PROGS)
 
 check: $(TEST_PROGS) check-fuzzer
 	@if test X"$(cross_compiling)" != X"yes"; then \
-	    if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	    if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 		LC_ALL=C.UTF-8; export LC_ALL; \
 	    else \
 		LC_ALL=C; export LC_ALL; \
diff --git a/plugins/python/Makefile.in b/plugins/python/Makefile.in
index a4b71e57a..997eb479f 100644
--- a/plugins/python/Makefile.in
+++ b/plugins/python/Makefile.in
@@ -36,6 +36,7 @@ cross_compiling = @CROSS_COMPILING@
 # Compiler & tools to use
 CC = @CC@
 LIBTOOL = @LIBTOOL@
+GREP = @GREP@
 SED = @SED@
 AWK = @AWK@
 
@@ -227,7 +228,7 @@ check-fuzzer:
 
 check: $(TEST_PROGS) check-fuzzer
 	@if test X"$(cross_compiling)" != X"yes"; then \
-	    if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	    if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 		LC_ALL=C.UTF-8; export LC_ALL; \
 	    else \
 		LC_ALL=C; export LC_ALL; \
diff --git a/plugins/sudoers/Makefile.in b/plugins/sudoers/Makefile.in
index 037a7da84..29110dcfd 100644
--- a/plugins/sudoers/Makefile.in
+++ b/plugins/sudoers/Makefile.in
@@ -47,6 +47,7 @@ LIBTOOL = @LIBTOOL@
 SHA1SUM = @SHA1SUM@
 FLEX = @FLEX@
 YACC = @YACC@
+GREP = @GREP@
 SED = @SED@
 AWK = @AWK@
 
@@ -429,7 +430,7 @@ fuzz_policy_seed_corpus.zip:
 	rm -rf $$tdir
 
 run-fuzz_policy: fuzz_policy
-	if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 	    LC_ALL=C.UTF-8; export LC_ALL; \
 	else \
 	    LC_ALL=C; export LC_ALL; \
@@ -456,7 +457,7 @@ fuzz_sudoers_seed_corpus.zip:
 	rm -rf $$tdir
 
 run-fuzz_sudoers: fuzz_sudoers
-	if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 	    LC_ALL=C.UTF-8; export LC_ALL; \
 	else \
 	    LC_ALL=C; export LC_ALL; \
@@ -483,7 +484,7 @@ fuzz_sudoers_ldif_seed_corpus.zip:
 	rm -rf $$tdir
 
 run-fuzz_sudoers_ldif: fuzz_sudoers_ldif
-	if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 	    LC_ALL=C.UTF-8; export LC_ALL; \
 	else \
 	    LC_ALL=C; export LC_ALL; \
@@ -633,7 +634,7 @@ fuzz: run-fuzz_policy run-fuzz_sudoers run-fuzz_sudoers_ldif
 
 check-fuzzer: $(FUZZ_PROGS)
 	@if test X"$(cross_compiling)" != X"yes"; then \
-	    if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	    if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 		LC_ALL=C.UTF-8; export LC_ALL; \
 	    else \
 		LC_ALL=C; export LC_ALL; \
@@ -652,7 +653,7 @@ check-fuzzer: $(FUZZ_PROGS)
 
 check: $(TEST_PROGS) visudo testsudoers cvtsudoers check-fuzzer
 	@if test X"$(cross_compiling)" != X"yes"; then \
-	    if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	    if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 		LC_ALL=C.UTF-8; export LC_ALL; \
 	    else \
 		LC_ALL=C; export LC_ALL; \
diff --git a/src/Makefile.in b/src/Makefile.in
index f3a411f1b..d7178b75c 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -35,6 +35,7 @@ cross_compiling = @CROSS_COMPILING@
 # Compiler & tools to use
 CC = @CC@
 LIBTOOL = @LIBTOOL@
+GREP = @GREP@
 SED = @SED@
 AWK = @AWK@
 
@@ -330,7 +331,7 @@ check-fuzzer:
 
 check: $(TEST_PROGS) check-fuzzer
 	@if test X"$(cross_compiling)" != X"yes"; then \
-	    if locale -a 2>&1 | grep '^C.UTF-8$$' >/dev/null 2>&1; then \
+	    if locale -a 2>&1 | $(GREP) '^C.UTF-8$$' >/dev/null 2>&1; then \
 		LC_ALL=C.UTF-8; export LC_ALL; \
 	    else \
 		LC_ALL=C; export LC_ALL; \