diff --git a/meta/recipes-devtools/tcltk/tcl_9.1.0.bb b/meta/recipes-devtools/tcltk/tcl_9.1.0.bb
index 6e8a97c729..483722c0e3 100644
--- a/meta/recipes-devtools/tcltk/tcl_9.1.0.bb
+++ b/meta/recipes-devtools/tcltk/tcl_9.1.0.bb
@@ -78,14 +78,15 @@ do_compile_ptest() {
 	oe_runmake tcltest
 }
 
+# Override-specific skips; do_install_ptest needs the empty SKIP="" in run-ptest
+SKIPPED_TESTS = ""
+# Assumes locales other than provided by musl-locales
+SKIPPED_TESTS:append:libc-musl = " unixInit-3*"
+
 do_install_ptest() {
 	cp ${B}/tcltest ${D}${PTEST_PATH}
 	cp -r ${S}/tests ${D}${PTEST_PATH}
-}
-
-do_install_ptest:append:libc-musl () {
-	# Assumes locales other than provided by musl-locales
-	sed -i '/SKIP="$SKIP.*$/a # unixInit-3* is suppressed due to hardcoded locale assumptions\nSKIP="$SKIP unixInit-3\\\*"' ${D}${PTEST_PATH}/run-ptest
+	sed -i -e 's|^SKIP=""$|SKIP="${SKIPPED_TESTS}"|' ${D}${PTEST_PATH}/run-ptest
 }
 
 # Fix some paths that might be used by Tcl extensions
diff --git a/meta/recipes-devtools/tcltk8/tcl8_8.6.18.bb b/meta/recipes-devtools/tcltk8/tcl8_8.6.18.bb
index 2094c9935a..07f3ad4592 100644
--- a/meta/recipes-devtools/tcltk8/tcl8_8.6.18.bb
+++ b/meta/recipes-devtools/tcltk8/tcl8_8.6.18.bb
@@ -79,14 +79,15 @@ do_compile_ptest() {
 	oe_runmake tcltest
 }
 
+# Override-specific skips; do_install_ptest needs the empty SKIP="" in run-ptest
+SKIPPED_TESTS = ""
+# Assumes locales other than provided by musl-locales
+SKIPPED_TESTS:append:libc-musl = " unixInit-3*"
+
 do_install_ptest() {
 	cp ${B}/tcltest ${D}${PTEST_PATH}
 	cp -r ${S}/tests ${D}${PTEST_PATH}
-}
-
-do_install_ptest:append:libc-musl () {
-	# Assumes locales other than provided by musl-locales
-	sed -i '/SKIP="$SKIP.*$/a # unixInit-3* is suppressed due to hardcoded locale assumptions\nSKIP="$SKIP unixInit-3\\\*"' ${D}${PTEST_PATH}/run-ptest
+	sed -i -e 's|^SKIP=""$|SKIP="${SKIPPED_TESTS}"|' ${D}${PTEST_PATH}/run-ptest
 }
 
 # Fix some paths that might be used by Tcl extensions