Index: openacs-4/packages/acs-admin/tcl/acs-admin-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-admin/tcl/acs-admin-procs.tcl,v
diff -u -r1.2.2.7 -r1.2.2.8
--- openacs-4/packages/acs-admin/tcl/acs-admin-procs.tcl	11 Oct 2022 13:28:06 -0000	1.2.2.7
+++ openacs-4/packages/acs-admin/tcl/acs-admin-procs.tcl	25 Feb 2024 16:13:41 -0000	1.2.2.8
@@ -47,7 +47,7 @@
                         # Check expiration of the certificate using the
                         # "openssl" command line tool.
                         #
-                        set notAfter [exec openssl x509 -enddate -noout -in $certfile]
+                        set notAfter [exec $openssl x509 -enddate -noout -in $certfile]
                         regexp {notAfter=(.*)$} $notAfter . date
                         set days [expr {([clock scan $date] - [clock seconds])/(60*60*24.0)}]
                         set info "Certificate $certfile will expire in [format %.1f $days] days"
Index: openacs-4/packages/acs-automated-testing/tcl/aa-test-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-automated-testing/tcl/aa-test-procs.tcl,v
diff -u -r1.79.2.67 -r1.79.2.68
--- openacs-4/packages/acs-automated-testing/tcl/aa-test-procs.tcl	9 Jan 2024 16:19:03 -0000	1.79.2.67
+++ openacs-4/packages/acs-automated-testing/tcl/aa-test-procs.tcl	25 Feb 2024 16:13:42 -0000	1.79.2.68
@@ -2295,7 +2295,7 @@
     set report_dir [aa_test::xml_report_dir]
     if { [file isdirectory $report_dir] } {
 
-        set hostname [exec hostname]
+        set hostname [exec [::utl::which hostname]]
         set server [ns_info server]
         set file_path "$report_dir/${hostname}-${server}-testreport.xml"
 
Index: openacs-4/packages/acs-tcl/tcl/http-client-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/tcl/http-client-procs.tcl,v
diff -u -r1.30.2.28 -r1.30.2.29
--- openacs-4/packages/acs-tcl/tcl/http-client-procs.tcl	23 Jun 2023 12:39:26 -0000	1.30.2.28
+++ openacs-4/packages/acs-tcl/tcl/http-client-procs.tcl	25 Feb 2024 16:13:42 -0000	1.30.2.29
@@ -1554,7 +1554,7 @@
 } {
     Gets Curl's version number.
 } {
-    set version [lindex [exec curl --version] 1]
+    set version [lindex [exec [::util::which curl] --version] 1]
 }
 
 ad_proc -private util::http::curl::version {
@@ -1762,7 +1762,7 @@
 
     ## Issuing of the request
 
-    set cmd [list exec curl -s]
+    set cmd [list exec [::util::which curl] -s]
 
     if {$spool_p} {
         set spool_file [ad_tmpnam]
Index: openacs-4/packages/caldav/tcl/caldav-interface-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/caldav/tcl/caldav-interface-procs.tcl,v
diff -u -r1.1.2.7 -r1.1.2.8
--- openacs-4/packages/caldav/tcl/caldav-interface-procs.tcl	22 Dec 2022 02:51:37 -0000	1.1.2.7
+++ openacs-4/packages/caldav/tcl/caldav-interface-procs.tcl	25 Feb 2024 16:13:42 -0000	1.1.2.8
@@ -558,7 +558,7 @@
         # GN TODO: don't hardcode timezone
 
         set timezone [lang::system::timezone]
-        set date_info [exec date "+%Z %z"]
+        set date_info [exec [util::which date] "+%Z %z"]
         set TZNAME [linex $date_info 0]
         set default_offset [linex $date_info 1]
 
@@ -578,7 +578,7 @@
         #
         try {
             set year [clock format [clock seconds] -format %Y ]
-            set lines [exec zdump -v [lang::system::timezone] | fgrep $year]
+            set lines [exec [::util::which zdump] -v [lang::system::timezone] | fgrep $year]
             foreach l [split $lines \n] {
                 #
                 # Compute date difference in seconds