diff --git a/iasha1check b/iasha1check
index 7883e3c..37ca167 100755
--- a/iasha1check
+++ b/iasha1check
@@ -42,7 +42,9 @@ echo
 
 echo "SHA-1 comparison:"
 sha1sum -c < <(printf "%s\n" "${iasha1sums[@]}") > >(perl -pe 's,^(.*)(?<!: OK)$,'"${RED}"'\1'"${RESET}"',; s,: OK$,: '"${GREEN}OK${RESET}"',; s,^,  ,') 2>&1
-if [[ $? -eq 0 ]]
+shast=$?
+wait  # Wait for Perl to finish; Bash 4.4+ only
+if [[ ${shast} -eq 0 ]]
 then
 	echo "SHA-1 comparison: ${GREEN}OK${RESET}"
 else