Index: misctools/become
===================================================================
--- misctools/become
+++ misctools/become
@@ -1,6 +1,8 @@
 #!/bin/bash
 #
 # Copyright © 2013 Marc-André Pelletier <mpelletier@wikimedia.org>
+#             2024 Marc-André Pelletier <mpelletier@wikimedia.org>
+#                  Valerio Bozzolan <boz@reyboz.it>
 #
 # Permission to use, copy, modify, and/or distribute this software for any
 # purpose with or without fee is hereby granted, provided that the above
@@ -15,25 +17,38 @@
 # OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #
 
-prefix=$(/bin/cat /etc/wmcs-project)
-if [ $# -lt 1 -o "$1" = "--help" ]; then
-  echo "usage: $(basename $0) <toolname> [command [args...]]" >&2
-  exit 1
+# NOTE: This script relies on the Bash feature "$EUID".
+#       So, the shebang cannot use /bin/sh.
+
+# Be strict. In case of an error, die without proceeding.
+set -e
+
+# This contains a short string. Example: "tools".
+prefix=$(< /etc/wmcs-project)
+
+# Require the right number of arguments.
+if [ $# -lt 1 ] || [ "$1" = "--help" ]; then
+    echo "usage: $(basename "$0") <toolname> [command [args...]]" >&2
+    exit 1
 fi
+
+# This is the tool name. Example: "croptool".
 tool="$1"
+
+# Discard the first argument, that is, the name of this script.
 shift
 
 # Test whether the given tool exists.
 if ! id "$prefix.$tool" >/dev/null 2>&1 || ! [ -d "/data/project/$tool" ]; then
-  echo "$(basename $0): no such tool '$tool'" >&2
-  exit 1
+    echo "$(basename "$0"): no such tool '$tool'" >&2
+    exit 1
 fi
 
 # Test whether the user is a member of the tool's group in this
 # session unless the user is root.
-if [ $EUID -ne 0 ] && ! echo " $(groups) " | fgrep -q " $prefix.$tool "; then
+if [ $EUID -ne 0 ] && ! echo " $(groups) " | grep --fixed-strings --quiet " $prefix.$tool "; then
     # Test whether the user is a member of the tool's group at all.
-    if echo ",$(getent group "$prefix.$tool" | cut -d : -f 4)," | fgrep -q ",$(id -nu),"; then
+    if echo ",$(getent group "$prefix.$tool" | cut -d : -f 4)," | grep --fixed-strings --quiet ",$(id -nu),"; then
         echo "You were added to the group $prefix.$tool after you started this login session." >&2
         echo "You need to log out and in again to be able to \"become $tool\"." >&2
     else
@@ -45,4 +60,4 @@
 fi
 
 # Execute sudo.
-exec /usr/bin/sudo -niu "$prefix.$tool" "$@"
+exec /usr/bin/sudo --non-interactive --login --user="$prefix.$tool" "$@"