diff --git a/SOURCES/which2.sh b/SOURCES/which2.sh
index 2b8b20a..6ef7979 100644
--- a/SOURCES/which2.sh
+++ b/SOURCES/which2.sh
@@ -1,18 +1,19 @@
 # shellcheck shell=sh
 # Initialization script for bash, sh, mksh and ksh
 
-_declare="declare -f"
-_opt="-f"
-_shell="$(basename $SHELL)"
+which_declare="declare -f"
+which_opt="-f"
+which_shell="$(cat /proc/$$/comm)"
 
-if [ "$_shell" = "ksh" ] || [ "$_shell" = "mksh" ] || [ "$_shell" = "zsh" ] ; then
-  _declare="typeset -f"
-  _opt=""
+if [ "$which_shell" = "ksh" ] || [ "$which_shell" = "mksh" ] || [ "$which_shell" = "zsh" ] ; then
+  which_declare="typeset -f"
+  which_opt=""
 fi
  
 which ()
 {
-(alias; eval ${_declare}) | /usr/bin/which --tty-only --read-alias --read-functions --show-tilde --show-dot "$@"
+(alias; eval ${which_declare}) | /usr/bin/which --tty-only --read-alias --read-functions --show-tilde --show-dot "$@"
 }
 
-export ${_opt} which
+export which_declare
+export ${which_opt} which
diff --git a/SPECS/which.spec b/SPECS/which.spec
index 299703c..46d38a9 100644
--- a/SPECS/which.spec
+++ b/SPECS/which.spec
@@ -1,7 +1,7 @@
 Summary: Displays where a particular program in your path is located
 Name: which
 Version: 2.21
-Release: 14%{?dist}
+Release: 16%{?dist}
 License: GPLv3
 Source0: http://ftp.gnu.org/gnu/which/%{name}-%{version}.tar.gz
 Source1: which2.sh
@@ -41,6 +41,13 @@ rm -f $RPM_BUILD_ROOT%{_infodir}/dir
 %{_mandir}/man1/which.1*
 
 %changelog
+* Wed May 05 2021 Than Ngo <than@redhat.com> - 2.21-16
+- Related: #1940468, fixed unbound variable
+
+
+* Fri Apr 30 2021 Than Ngo <than@redhat.com> - 2.21-15
+- Related: #1940468, fix error when the user runs which in bash with strict bash environment
+
 * Tue Mar 23 2021 Than Ngo <than@redhat.com> - 2.21-14
 - Related: #1940468, fix regression if SHELL=zsh