--- a/autoopts/mk-tpl-config.sh
+++ b/autoopts/mk-tpl-config.sh
@@ -98,7 +98,7 @@ fix_scripts() {
         st=`sed 1q $f`
 
         case "$st" in
-        *perl ) echo '#!' `which perl`
+        *perl ) echo '#!' `command -v perl`
                  sed 1d $f
                  ;;
 
@@ -124,7 +124,7 @@ find_shell_prog() {
     case `uname -s` in
     SunOS )
       while : ; do
-        POSIX_SHELL=`which bash`
+        POSIX_SHELL=`command -v bash`
         test -x "${POSIX_SHELL}" && break
         POSIX_SHELL=/usr/xpg4/bin/sh
         test -x "${POSIX_SHELL}" && break
@@ -139,7 +139,7 @@ find_cat_prog() {
     do
         \unalias -a
         unset -f command cat which
-        POSIX_CAT=`which cat`
+        POSIX_CAT=`command -v cat`
         test -x "$POSIX_CAT" && break
         POSIX_CAT=`
             PATH=\`command -p getconf CS_PATH\`
--- a/autoopts/test/defs.in
+++ b/autoopts/test/defs.in
@@ -40,7 +40,7 @@ cfg_vals()
     if test "X$BASH_VERSION" = X
     then
       # On Solaris, make certain we do not use /bin/sh
-      sh=`which bash`
+      sh=`command -v bash`
       test "X$sh" = X && sh=/usr/xpg4/bin/sh
       BASH_VERSION=not-good-enough
       export BASH_VERSION
--- a/autoopts/tpl/agtexi-cmd.tpl
+++ b/autoopts/tpl/agtexi-cmd.tpl
@@ -779,7 +779,7 @@ DEFINE initialization                   =][=
 =][= # END-BUILDTREE-ISMS
 
 (shell "CLexe=`echo ${AGexe} | sed 's@/autogen@/columns@'`
-       test -x \"${CLexe}\" || CLexe=`which columns`")
+       test -x \"${CLexe}\" || CLexe=`command -v columns`")
 
 # END-INSTALL-ONLY-CODE =][=
 
--- a/autoopts/tpl/cmd-doc.tlib
+++ b/autoopts/tpl/cmd-doc.tlib
@@ -42,7 +42,7 @@
 :+][+: # END-BUILDTREE-ISMS
 
 (shell "CLexe=`echo ${AGexe} | sed 's@/autogen@/columns@'`
-       test -x \"${CLexe}\" || CLexe=`which columns`")
+       test -x \"${CLexe}\" || CLexe=`command -v columns`")
 
 # END-INSTALL-ONLY-CODE :+][+:
 
--- a/autoopts/tpl/def2pot.tpl
+++ b/autoopts/tpl/def2pot.tpl
@@ -68,7 +68,7 @@ ENDDEF                                                       =][=
 =][= # END-BUILDTREE-ISMS
 
 (shell "CLexe=`echo ${AGexe} | sed 's@/autogen@/columns@'`
-       test -x \"${CLexe}\" || CLexe=`which columns`")
+       test -x \"${CLexe}\" || CLexe=`command -v columns`")
 
 # END-INSTALL-ONLY-CODE =][= #
 
--- a/autoopts/tpl/getopt.tpl
+++ b/autoopts/tpl/getopt.tpl
@@ -81,7 +81,7 @@ CASE (suffix) +][+
 # END-BUILDTREE-ISMS the following code is for installed version:
     agopts=
     aocfg=`echo ${AGexe} | sed 's@/[^/]*$@@'`/autoopts-config
-    test -x "${aocfg}" || aocfg=`which autoopts-config`
+    test -x "${aocfg}" || aocfg=`command -v autoopts-config`
     tarfile=`${aocfg} libsrc`
 
 # END-INSTALL-ONLY-CODE +]
--- a/autoopts/tpl/options.tpl
+++ b/autoopts/tpl/options.tpl
@@ -39,7 +39,7 @@ c
 =][= # END-BUILDTREE-ISMS
 
 (shell "CLexe=`echo ${AGexe} | sed 's@/autogen@/columns@'`
-       test -x \"${CLexe}\" || CLexe=`which columns`")
+       test -x \"${CLexe}\" || CLexe=`command -v columns`")
 
 # END-INSTALL-ONLY-CODE     =][=
 
--- a/autoopts/tpl/usage.tlib
+++ b/autoopts/tpl/usage.tlib
@@ -34,7 +34,7 @@
 =][= # END-BUILDTREE-ISMS
 
 (shell "CLexe=`echo ${AGexe} | sed 's@/autogen@/columns@'`
-       test -x \"${CLexe}\" || CLexe=`which columns`")
+       test -x \"${CLexe}\" || CLexe=`command -v columns`")
 
 # END-INSTALL-ONLY-CODE =][=
 
--- a/config/ag_macros.m4
+++ b/config/ag_macros.m4
@@ -505,7 +505,7 @@ AC_DEFUN([AG_ENABLE_DEBUG],[
         [Define this if wanting autogen debugging])
     AC_DEFINE([DEBUG_ENABLED], [1],
           [Define this if debugging is enabled])
-    [f=`which dmalloc 2>/dev/null`
+    [f=`command -v dmalloc 2>/dev/null`
     test -n "$f" && LIBS="${LIBS} -ldmalloc"]
   fi
 
--- a/config/bootstrap.shlib
+++ b/config/bootstrap.shlib
@@ -47,16 +47,16 @@ case "${SHELL}" in
 *[akz]sh) : ;;
 *)
   while : ; do
-    SHELL=`which bash 2>/dev/null`
+    SHELL=`command -v bash 2>/dev/null`
     test -x "${SHELL}" && break
 
-    SHELL=`which ksh 2>/dev/null`
+    SHELL=`command -v ksh 2>/dev/null`
     test -x "${SHELL}" && break
 
     SHELL=/usr/xpg4/bin/sh
     test -x "${SHELL}" && break
 
-    SHELL=`which sh 2>/dev/null`
+    SHELL=`command -v sh 2>/dev/null`
     test -x "${SHELL}" && break
 
     die "unable to determine which shell to use"
--- a/config/libopts.m4
+++ b/config/libopts.m4
@@ -108,9 +108,9 @@ AC_DEFUN([INVOKE_LIBOPTS_MACROS_FIRST],[
   [while :
   do
       test -x "$POSIX_SHELL" && break
-      POSIX_SHELL=`which bash`
+      POSIX_SHELL=`command -v bash`
       test -x "$POSIX_SHELL" && break
-      POSIX_SHELL=`which dash`
+      POSIX_SHELL=`command -v dash`
       test -x "$POSIX_SHELL" && break
       POSIX_SHELL=/usr/xpg4/bin/sh
       test -x "$POSIX_SHELL" && break
--- a/config/mk-shdefs.in
+++ b/config/mk-shdefs.in
@@ -109,7 +109,7 @@ configure() {
     {
         cmd='`set -o | '${AWK}" '/^allexport/ {print \$2}'"\`
         cat <<- _EOF_
-		#! `which echo` this-file-should-be-sourced,-not-executed
+		#! `command -v echo` this-file-should-be-sourced,-not-executed
 		# -*- Mode: shell-script -*-
 
 		case "$cmd" in
--- a/configure.ac
+++ b/configure.ac
@@ -149,9 +149,9 @@ GDnam=getdefs${ac_exeext}
 CLnam=columns${ac_exeext}
 if test "X$cross_compiling" = Xyes
 then
-  AGexe=`which ${AGnam}`
-  GDexe=`which ${GDnam}`
-  CLexe=`which ${CLnam}`
+  AGexe=`command -v ${AGnam}`
+  GDexe=`command -v ${GDnam}`
+  CLexe=`command -v ${CLnam}`
 else
   AGexe=${ag_top_builddir}/agen5/${AGnam}
   GDexe=${ag_top_builddir}/getdefs/${GDnam}
--- a/doc/mk-agen-texi.sh
+++ b/doc/mk-agen-texi.sh
@@ -65,7 +65,7 @@ set_config_values()
   nl='
 ' ht='	'
   . ${top_builddir}/config/shdefs
-  : ${MAKE=`which make`}
+  : ${MAKE=`command -v make`}
   : ${srcdir=`pwd`}
   srcdir=`cd ${srcdir} >/dev/null ; pwd`
   INCLUDES="${DEFS} "`
--- a/getdefs/test/defs
+++ b/getdefs/test/defs
@@ -40,7 +40,7 @@ cfg_vals()
     if test "X$BASH_VERSION" = X
     then
       # On Solaris, make certain we do not use /bin/sh
-      sh=`which bash`
+      sh=`command -v bash`
       test "X$sh" = X && sh=/usr/xpg4/bin/sh
       BASH_VERSION=not-good-enough
       export BASH_VERSION