From 5db964e7edc3283d7f0a0bb5f55e749743402d69 Mon Sep 17 00:00:00 2001
From: Bertho Stultiens <bertho@vagrearg.org>
Date: Thu, 30 Jan 2025 22:53:20 +0100
Subject: [PATCH 1/4] Fix most cd || exit problems noted by shellcheck. Also
 includes missing double quotes and few other simple changes.

---
 .../animated-backdrop/animated-backdrop.demo  |  2 +-
 configs/apps/gladevcp/by-widget/combobox.demo |  2 +-
 .../by-widget/combobox_manual_list.demo       |  2 +-
 .../apps/gladevcp/by-widget/radiobutton.demo  |  2 +-
 .../apps/gladevcp/by-widget/sourceview.demo   |  2 +-
 .../apps/gladevcp/by-widget/spinbutton.demo   |  2 +-
 .../class-callback/class_callback.demo        |  2 +-
 .../gladevcp/colored-label/coloredlabel.demo  |  2 +-
 configs/apps/gladevcp/complex/complex.demo    |  2 +-
 configs/apps/gladevcp/glade-manual.demo       |  2 +-
 configs/apps/gladevcp/gladevcp-test.demo      |  2 +-
 .../apps/gladevcp/helloWorld/helloworld.demo  |  2 +-
 .../mdi-command-example/owordsub.demo         |  2 +-
 .../gladevcp/mdi-command-example/speed.demo   |  2 +-
 .../mdi-command-example/whoareyou.demo        |  2 +-
 .../simple-callback/simple-callback.demo      |  2 +-
 .../apps/gladevcp/templates/classhandler.demo |  2 +-
 .../classhandler_persistent.demo_notworking   |  2 +-
 .../gladevcp/templates/functionhandler.demo   |  2 +-
 configs/apps/halrun/halrun.demo               | 23 ++++++-----
 configs/apps/xhc-hb04/xhc-hb04-layout1.demo   |  2 +-
 configs/apps/xhc-hb04/xhc-hb04-layout2.demo   |  2 +-
 configs/apps/xhc-hb04/xhc-hb04.demo           |  2 +-
 configs/apps/xhc-hb04/xhc-hb04.sh             | 10 ++---
 .../sim/axis/gladevcp/set-param-from-ini.sh   |  2 +-
 scripts/hal_demo                              | 32 +++++++++------
 scripts/make-docs-pdf-index                   | 20 +++++----
 scripts/pyvcp_demo                            | 41 ++++++++++---------
 scripts/swish                                 | 17 ++++----
 29 files changed, 102 insertions(+), 87 deletions(-)

diff --git a/configs/apps/gladevcp/animated-backdrop/animated-backdrop.demo b/configs/apps/gladevcp/animated-backdrop/animated-backdrop.demo
index 767e1fd3b32..c6192efc4d0 100755
--- a/configs/apps/gladevcp/animated-backdrop/animated-backdrop.demo
+++ b/configs/apps/gladevcp/animated-backdrop/animated-backdrop.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u ./cairodraw.py ./cairodraw.ui
diff --git a/configs/apps/gladevcp/by-widget/combobox.demo b/configs/apps/gladevcp/by-widget/combobox.demo
index 188ddcb2610..677a86d9bf8 100755
--- a/configs/apps/gladevcp/by-widget/combobox.demo
+++ b/configs/apps/gladevcp/by-widget/combobox.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u combobox.py combobox.ui
diff --git a/configs/apps/gladevcp/by-widget/combobox_manual_list.demo b/configs/apps/gladevcp/by-widget/combobox_manual_list.demo
index 7f8ddc7843f..afd51ecdccf 100755
--- a/configs/apps/gladevcp/by-widget/combobox_manual_list.demo
+++ b/configs/apps/gladevcp/by-widget/combobox_manual_list.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u ./combobox_manual_list.py ./combobox_manual_list.ui
diff --git a/configs/apps/gladevcp/by-widget/radiobutton.demo b/configs/apps/gladevcp/by-widget/radiobutton.demo
index 8de1bf118fb..a32d62beb5f 100755
--- a/configs/apps/gladevcp/by-widget/radiobutton.demo
+++ b/configs/apps/gladevcp/by-widget/radiobutton.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u ./radio.py ./radio.ui
diff --git a/configs/apps/gladevcp/by-widget/sourceview.demo b/configs/apps/gladevcp/by-widget/sourceview.demo
index 24aa5d253fe..1b136b0a768 100755
--- a/configs/apps/gladevcp/by-widget/sourceview.demo
+++ b/configs/apps/gladevcp/by-widget/sourceview.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u ./sourceview.py ./sourceview.ui
diff --git a/configs/apps/gladevcp/by-widget/spinbutton.demo b/configs/apps/gladevcp/by-widget/spinbutton.demo
index 2f1414a5d85..450c8b8dd9d 100755
--- a/configs/apps/gladevcp/by-widget/spinbutton.demo
+++ b/configs/apps/gladevcp/by-widget/spinbutton.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u spinbutton.py spinbutton.ui
diff --git a/configs/apps/gladevcp/class-callback/class_callback.demo b/configs/apps/gladevcp/class-callback/class_callback.demo
index 03121a0227b..322c261315b 100755
--- a/configs/apps/gladevcp/class-callback/class_callback.demo
+++ b/configs/apps/gladevcp/class-callback/class_callback.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u ./class_callback.py -H ./class_callback.hal ./class_callback.ui
diff --git a/configs/apps/gladevcp/colored-label/coloredlabel.demo b/configs/apps/gladevcp/colored-label/coloredlabel.demo
index 489198f4b2b..282dc028570 100755
--- a/configs/apps/gladevcp/colored-label/coloredlabel.demo
+++ b/configs/apps/gladevcp/colored-label/coloredlabel.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u ./coloredlabel.py -H ./coloredlabel.hal ./coloredlabel.ui
diff --git a/configs/apps/gladevcp/complex/complex.demo b/configs/apps/gladevcp/complex/complex.demo
index 4443609d401..180ba23c52c 100755
--- a/configs/apps/gladevcp/complex/complex.demo
+++ b/configs/apps/gladevcp/complex/complex.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u ./complex.py -H ./complex.hal ./complex.ui
diff --git a/configs/apps/gladevcp/glade-manual.demo b/configs/apps/gladevcp/glade-manual.demo
index 91a14eee1f1..c402750cb23 100755
--- a/configs/apps/gladevcp/glade-manual.demo
+++ b/configs/apps/gladevcp/glade-manual.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo ./glade-manual.ui
diff --git a/configs/apps/gladevcp/gladevcp-test.demo b/configs/apps/gladevcp/gladevcp-test.demo
index 4f2c4fb0918..42895631f84 100755
--- a/configs/apps/gladevcp/gladevcp-test.demo
+++ b/configs/apps/gladevcp/gladevcp-test.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo ./gladevcp-test.ui
diff --git a/configs/apps/gladevcp/helloWorld/helloworld.demo b/configs/apps/gladevcp/helloWorld/helloworld.demo
index b7e7dd447f9..34373b6ba41 100755
--- a/configs/apps/gladevcp/helloWorld/helloworld.demo
+++ b/configs/apps/gladevcp/helloWorld/helloworld.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -H ./hw.hal ./hw.ui
diff --git a/configs/apps/gladevcp/mdi-command-example/owordsub.demo b/configs/apps/gladevcp/mdi-command-example/owordsub.demo
index cf8f2e6ba25..7aaed73a548 100755
--- a/configs/apps/gladevcp/mdi-command-example/owordsub.demo
+++ b/configs/apps/gladevcp/mdi-command-example/owordsub.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo ./owordsub.ui
diff --git a/configs/apps/gladevcp/mdi-command-example/speed.demo b/configs/apps/gladevcp/mdi-command-example/speed.demo
index 01cada7e8bd..c272c32d6e6 100755
--- a/configs/apps/gladevcp/mdi-command-example/speed.demo
+++ b/configs/apps/gladevcp/mdi-command-example/speed.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo ./speed.ui
diff --git a/configs/apps/gladevcp/mdi-command-example/whoareyou.demo b/configs/apps/gladevcp/mdi-command-example/whoareyou.demo
index b4d69e4d296..f08317c6597 100755
--- a/configs/apps/gladevcp/mdi-command-example/whoareyou.demo
+++ b/configs/apps/gladevcp/mdi-command-example/whoareyou.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo ./whoareyou.ui
diff --git a/configs/apps/gladevcp/simple-callback/simple-callback.demo b/configs/apps/gladevcp/simple-callback/simple-callback.demo
index 8a627fafce3..20ec4ce1356 100755
--- a/configs/apps/gladevcp/simple-callback/simple-callback.demo
+++ b/configs/apps/gladevcp/simple-callback/simple-callback.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u ./simplecallback.py ./simplecallback.ui
diff --git a/configs/apps/gladevcp/templates/classhandler.demo b/configs/apps/gladevcp/templates/classhandler.demo
index ea800f6bd4a..bb0cb66f836 100755
--- a/configs/apps/gladevcp/templates/classhandler.demo
+++ b/configs/apps/gladevcp/templates/classhandler.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u ./classhandler.py ./button.ui
diff --git a/configs/apps/gladevcp/templates/classhandler_persistent.demo_notworking b/configs/apps/gladevcp/templates/classhandler_persistent.demo_notworking
index bd27c7fa5bb..5b3cdde88bd 100755
--- a/configs/apps/gladevcp/templates/classhandler_persistent.demo_notworking
+++ b/configs/apps/gladevcp/templates/classhandler_persistent.demo_notworking
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u ./classhandler_persistent.py  -U debug=2 -U "print 'debug=%d' % debug"  ./button.ui
diff --git a/configs/apps/gladevcp/templates/functionhandler.demo b/configs/apps/gladevcp/templates/functionhandler.demo
index 17ab3158bff..bb613484231 100755
--- a/configs/apps/gladevcp/templates/functionhandler.demo
+++ b/configs/apps/gladevcp/templates/functionhandler.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 gladevcp_demo -u ./functionhandler.py ./button.ui
diff --git a/configs/apps/halrun/halrun.demo b/configs/apps/halrun/halrun.demo
index 09101691590..fdc876a2642 100755
--- a/configs/apps/halrun/halrun.demo
+++ b/configs/apps/halrun/halrun.demo
@@ -1,11 +1,12 @@
 #!/bin/bash
 
-prog=$(basename $0)
+prog=$(basename "$0")
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
 HALFILE="$thisdir"/help.hal
 
-cd ;# so user can use halcmd 'save' to create a file
+# Don't care if cd succeeds. Just so user can use halcmd 'save' to create a file in $HOME
+cd || true
 
 function popup () {
   msg="$*"
@@ -21,9 +22,9 @@ EOF
 } ;# popup
 
 
-[ X"$TERM" = Xdumb ] && TERM=xterm
-[ -x "$(which $COLORTERM)" ] && TERM=$COLORTERM
-[ -z $TERM ] && TERM=xterm
+[ "$TERM" = "dumb" ] && TERM=xterm
+[ -x "$(which "$COLORTERM")" ] && TERM=$COLORTERM
+[ -z "$TERM" ] && TERM=xterm
 
 # wip: xterm is well-behaved, some other terminals are not
 # for now: force to xterm
@@ -33,11 +34,11 @@ REALTIME=$(linuxcnc_var REALTIME)
 # make sure TERM uses the expected halrun (rip or install)
 HALRUN=$(which halrun)
 
-if [ ! -z "$debug" ] ; then
-  echo COLORTERM=$COLORTERM
-  echo TERM=$TERM
-  echo HALRUN=$HALRUN
-  echo REALTIME=$REALTIME
+if [ -n "$debug" ] ; then
+  echo "COLORTERM=$COLORTERM"
+  echo "TERM=$TERM"
+  echo "HALRUN=$HALRUN"
+  echo "REALTIME=$REALTIME"
 fi
 
 if $REALTIME status >/dev/null ; then
@@ -51,7 +52,7 @@ fi
 # terminate any other halrun instance:
 $HALRUN -U >/dev/null 2>&1
 
-if [ X"$TERM" = Xxterm ] ; then
+if [ "$TERM" = "xterm" ] ; then
   $TERM -geometry 80x40 \
         -sb \
         -fg black -bg ivory2 \
diff --git a/configs/apps/xhc-hb04/xhc-hb04-layout1.demo b/configs/apps/xhc-hb04/xhc-hb04-layout1.demo
index 8aa55a203f0..63841fcd3eb 100755
--- a/configs/apps/xhc-hb04/xhc-hb04-layout1.demo
+++ b/configs/apps/xhc-hb04/xhc-hb04-layout1.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 ./xhc-hb04.sh layout1
diff --git a/configs/apps/xhc-hb04/xhc-hb04-layout2.demo b/configs/apps/xhc-hb04/xhc-hb04-layout2.demo
index f5c4ef638d8..6371ad5905b 100755
--- a/configs/apps/xhc-hb04/xhc-hb04-layout2.demo
+++ b/configs/apps/xhc-hb04/xhc-hb04-layout2.demo
@@ -2,6 +2,6 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 ./xhc-hb04.sh layout2
diff --git a/configs/apps/xhc-hb04/xhc-hb04.demo b/configs/apps/xhc-hb04/xhc-hb04.demo
index 594b43475c5..e890bb7c76d 100755
--- a/configs/apps/xhc-hb04/xhc-hb04.demo
+++ b/configs/apps/xhc-hb04/xhc-hb04.demo
@@ -2,7 +2,7 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 # use default layout
 ./xhc-hb04.sh
diff --git a/configs/apps/xhc-hb04/xhc-hb04.sh b/configs/apps/xhc-hb04/xhc-hb04.sh
index cadabe41c20..347655a5ea6 100755
--- a/configs/apps/xhc-hb04/xhc-hb04.sh
+++ b/configs/apps/xhc-hb04/xhc-hb04.sh
@@ -2,14 +2,14 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir"
+cd "$thisdir" || exit
 
 LAYOUT=${1:-""}
 
-[ -x "$(which $COLORTERM)" ] && TERM=$COLORTERM
-[ -z $TERM ] && TERM=xterm
+[ -x "$(which "$COLORTERM")" ] && TERM="$COLORTERM"
+[ -z "$TERM" ] && TERM=xterm
 # when invoked from Application menu and RIP, may have TERM=dumb
-[ x"$TERM" = xdumb ] && TERM=xterm
+[ "$TERM" = "dumb" ] && TERM=xterm
 
 XHC_HB04=$(which xhc-hb04)
 HALLIB_DIR=$(linuxcnc_var HALLIB_DIR)
@@ -20,7 +20,7 @@ case $LAYOUT in
 esac
 dashI="-I $CFG"
 
-if [ ! -z "$debug" ] ; then
+if [ -n "$debug" ] ; then
   echo "COLORTERM=$COLORTERM"
   echo "TERM=$TERM"
   echo "XHC_HB04=$XHC_HB04"
diff --git a/configs/sim/axis/gladevcp/set-param-from-ini.sh b/configs/sim/axis/gladevcp/set-param-from-ini.sh
index d9277f82f82..03604e10f5f 100755
--- a/configs/sim/axis/gladevcp/set-param-from-ini.sh
+++ b/configs/sim/axis/gladevcp/set-param-from-ini.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-cd $(dirname $::argv0)
+cd "$(dirname "$0")" || { echo "E: Could not change directory to '$(dirname "$0")'"; exit 1; }
 
 gladevcp -u ./meter_scale.py ./meter_scale.ui &
 
diff --git a/scripts/hal_demo b/scripts/hal_demo
index d043eb78535..6591d65a2e5 100755
--- a/scripts/hal_demo
+++ b/scripts/hal_demo
@@ -18,7 +18,7 @@
 #    
 # Copyright (c) 2004-2009 All rights reserved.
 #*******************************************************************/
-if [ ! $1 ] ; then
+if [ -z "$1" ] ; then
     echo "Usage:  scripts/hal_demo <demo_name>"
     echo "Run from the emc2 directory only"
     # print the list of demos
@@ -28,7 +28,7 @@ fi
 #
 # the first demo isn't a real demo - it simply lists all the demos
 #
-if [ $1 = list ] ; then
+if [ "$1" = "list" ] ; then
     echo "Available demos are:"
     echo "  list - prints this list"
     echo "  load - loads hal core modules"
@@ -44,10 +44,10 @@ fi
 #
 # here is the "load" command
 #
-if [ $1 = load ] ; then
+if [ "$1" = "load" ] ; then
     # load the rtos and rtapi
     if ! scripts/realtime start ; then
-        exit -1
+        exit 1
     fi
     # done
     echo "RTAPI core loaded"
@@ -56,12 +56,12 @@ fi
 #
 # here is the "unload" command
 #
-if [ $1 = unload ] ; then
+if [ "$1" = "unload" ] ; then
     # unload any left-over modules
     bin/halcmd unloadrt all
     # unload the rtos and rtapi
     if ! scripts/realtime stop ; then
-        exit -1
+        exit 1
     fi
     # done
     echo "RTAPI core unloaded"
@@ -71,17 +71,19 @@ fi
 # We're almost ready for the real demos, first we must
 # make sure the rtapi core is loaded
 #
-HAL_LIB_STR=`/sbin/lsmod | awk '{print $1}' | grep -x hal_lib `
-if [ ! "$HAL_LIB_STR" ] ; then
+HAL_LIB_STR=$(/sbin/lsmod | awk '{print $1}' | grep -x hal_lib)
+if [ -z "$HAL_LIB_STR" ] ; then
     echo "All of the demos require the RTAPI and HAL_LIB modules"
     echo "to be loaded.  Use 'hal_demo load' to load them."
-    exit -1
+    exit 1
 fi
 #
 # The first demo: "parport1" simply tests the parallel port
 # this one is a step by step, tutorial/intro to HAL concepts
 #
-if [ $1 = parport1 ] ; then
+# Don't care about read mangling backslashes, nothing read is used
+# shellcheck disable=SC2162
+if [ "$1" = "parport1" ] ; then
     echo "(Comments that are part of the demo are in parenthesis.)"
     echo "(This demo echos its commands to the screen so you can"
     echo " see what each step does.  Echoed commands start with '$')"
@@ -206,7 +208,9 @@ fi
 # and halmeter.
 # this one is also a step by step tutorial
 #
-if [ $1 = siggen ] ; then
+# Don't care about read mangling backslashes, nothing read is used
+# shellcheck disable=SC2162
+if [ "$1" = "siggen" ] ; then
     echo "(Comments that are part of the demo are in parenthesis.)"
     echo "(This demo echos its commands to the screen so you can"
     echo " see what each step does.  Echoed commands start with '$')"
@@ -288,7 +292,9 @@ fi
 # using siggen as a signal source.
 # this one is also a step by step tutorial
 #
-if [ $1 = scope ] ; then
+# Don't care about read mangling backslashes, nothing read is used
+# shellcheck disable=SC2162
+if [ "$1" = "scope" ] ; then
     echo "The first part of this demo is identical to the siggen"
     echo "demo.  Hit enter to get started"
     read
@@ -400,5 +406,5 @@ fi
 #
 echo "Sorry, there is no demo called '$1'"
 scripts/hal_demo
-exit -1
+exit 1
 
diff --git a/scripts/make-docs-pdf-index b/scripts/make-docs-pdf-index
index 177be4062b1..8037bc3e093 100755
--- a/scripts/make-docs-pdf-index
+++ b/scripts/make-docs-pdf-index
@@ -9,19 +9,23 @@ set -e
 # --show-toplevel` because when building from dsc we don't have a
 # git repo.
 TOPLEVEL=${PWD}/..
-cd ${TOPLEVEL}/docs
+cd "${TOPLEVEL}"/docs
 
-TITLE="LinuxCNC PDF docs ($(cat ${TOPLEVEL}/VERSION))"
+TITLE="LinuxCNC PDF docs ($(cat "${TOPLEVEL}"/VERSION))"
 
 rm -f index.html
 
-echo "<html>" >> index.html
-echo "<head><title>${TITLE}</title></head>" >> index.html
-echo "<body><h1>${TITLE}</h1><p>" >> index.html
+{
+    echo "<html>"
+    echo "<head><title>${TITLE}</title></head>"
+    echo "<body><h1>${TITLE}</h1><p>"
+} >> index.html
 
-for F in $(ls -1 *.pdf | sort); do
+for F in $(ls -1 ./*.pdf | sort); do
     echo "    <a href=\"${F}\">$F</a><br>" >> index.html
 done
 
-echo "</body>" >> index.html
-echo "</html>" >> index.html
+{
+    echo "</body>"
+    echo "</html>"
+} >> index.html
diff --git a/scripts/pyvcp_demo b/scripts/pyvcp_demo
index 6c43c299156..1fab35e347a 100755
--- a/scripts/pyvcp_demo
+++ b/scripts/pyvcp_demo
@@ -22,7 +22,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
-prog=$(basename $0)
+prog=$(basename "$0")
 
 function usage () {
   cat <<EOF
@@ -52,7 +52,7 @@ EOF
 REALTIME=$(linuxcnc_var REALTIME)
 $REALTIME status >/dev/null
 status=$?
-if [ $status = 0 ] ; then
+if [ "$status" = 0 ] ; then
   msg="$prog: Realtime is already active"
   echo "$msg"
   popup "$msg"
@@ -74,16 +74,18 @@ case $# in
     *) usage;;
 esac
 
-if [ ! -z "$debug" ] ; then
-  echo debug=$debug
-  echo REALTIME=$REALTIME
-  echo XMLFILE=$XMLFILE
-  echo HALFILE=$HALFILE
-  echo COMPNAME=$COMPNAME
+if [ -n "$debug" ] ; then
+  echo "debug=$debug"
+  echo "REALTIME=$REALTIME"
+  echo "XMLFILE=$XMLFILE"
+  echo "HALFILE=$HALFILE"
+  echo "COMPNAME=$COMPNAME"
 fi
 
-cd $(dirname "$XMLFILE") ;# to allow relative includes
-pyvcp -c $COMPNAME $XMLFILE &
+# to allow relative includes
+cd "$(dirname "$XMLFILE")" || { echo "E: Could not change directory to '$(dirname "$XMLFILE")'"; exit 1; }
+
+pyvcp -c "$COMPNAME" "$XMLFILE" &
 pyvcpjob=$!
 ct=0
 # wait for pins to be created before creating signals
@@ -91,7 +93,7 @@ while true ; do
    halcmd show|grep "${COMPNAME}.*ready" >/dev/null 2>&1
    status=$?
    sleep 1
-   if [ $status == 0 ] ; then
+   if [ "$status" = 0 ] ; then
       #echo "ready after ct=$ct"
       break
    fi
@@ -99,24 +101,25 @@ while true ; do
       echo "$0: hal-pyvcp startup failed"
       exit 1
    fi
-   ct=$(($ct+1))
+   ct=$((ct + 1))
 done
 
-cd $(dirname "$HALFILE") ;# so HALFILE can source relative files
+# so HALFILE can source relative files
+cd "$(dirname "$HALFILE")" || { echo "E: Could not change directory to '$(dirname "$HALFILE")'"; exit 1; }
 
 halmsg=/tmp/pyvcp_demo_halcmd.err
->|$halmsg
-halcmd -f $HALFILE >$halmsg 2>&1
+true >| "$halmsg"
+halcmd -f "$HALFILE" > "$halmsg" 2>&1
 halstatus=$?
-if [ $halstatus != 0 ] ; then
+if [ "$halstatus" != 0 ] ; then
   IFS=$'\n' # split lines
   newmsg=
   # put extra blank line between lines of output
-  for line in $(cat $halmsg) ; do
-newmsg="$newmsg
+  while read -r line; do
+    newmsg="$newmsg
 $line
 "
-  done
+  done < "$halmsg"
   popup "$newmsg"
   kill $pyvcpjob
   halrun -U
diff --git a/scripts/swish b/scripts/swish
index 59037dc5cd6..ac37748f3d3 100755
--- a/scripts/swish
+++ b/scripts/swish
@@ -11,10 +11,11 @@ fi
 
 case "$0" in
 	*/*) MYDIR="${0%/*}" ;;
-	*) MYDIR="`type -path $0`"; MYDIR="${MYDIR%/*}"
+	*) MYDIR="$(type -path "$0")"; MYDIR="${MYDIR%/*}"
 esac
 
-SRCDIR=$(cd "$MYDIR/../src"; pwd)
+SRCDIR=$(realpath "$MYDIR/../src")
+[ -d "$SRCDIR" ] || { echo "E: Cannot find directory '$SRCDIR'."; exit 1; }
 SWISHINDEX="$SRCDIR/.swishindex"
 
 function makerelative () {
@@ -64,7 +65,7 @@ EOF
 	exit 1
 }
 
-FORCEREBUILD=""
+FORCEREBUILD=0
 while getopts "hRF:" opt
 do
 	case "$opt" in
@@ -73,9 +74,9 @@ do
 	h|?)	usage ;;
 	esac
 done
-shift $(($OPTIND-1))
+shift $((OPTIND - 1))
 
-if [ "$FORCEREBUILD" -o ! -f "$SWISHINDEX" ]
+if [ "$FORCEREBUILD" -eq 1 ] || [ ! -f "$SWISHINDEX" ]
 then
 	make -C "$SRCDIR" swish || exit $?
 	if [ $# -eq 0 ]; then exit 0; fi
@@ -88,12 +89,12 @@ else
 	REGEXP="$1"
 fi
 
-if ! [ -z "$FILEFILTER" ]; then
-	swish-e -f $SWISHINDEX -H0 -x '<swishdocpath>\0' -w "$PAT" \
+if [ -n "$FILEFILTER" ]; then
+	swish-e -f "$SWISHINDEX" -H0 -x '<swishdocpath>\0' -w "$PAT" \
 		| $FILEFILTER | makerelative \
 		| xargs -0 grep -E -Hnis -e "$REGEXP"
 else
-	swish-e -f $SWISHINDEX -H0 -x '<swishdocpath>\0' -w "$PAT" \
+	swish-e -f "$SWISHINDEX" -H0 -x '<swishdocpath>\0' -w "$PAT" \
 		| makerelative \
 		| xargs -0 grep -E -Hnis -e "$REGEXP"
 fi

From eec772f1d40c77402accea0686e6d3dc7dfc66af Mon Sep 17 00:00:00 2001
From: Bertho Stultiens <bertho@vagrearg.org>
Date: Fri, 31 Jan 2025 12:31:07 +0100
Subject: [PATCH 2/4] Print message before exit on cd fail.

---
 configs/apps/xhc-hb04/xhc-hb04.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/configs/apps/xhc-hb04/xhc-hb04.sh b/configs/apps/xhc-hb04/xhc-hb04.sh
index 347655a5ea6..ca17bb73cb0 100755
--- a/configs/apps/xhc-hb04/xhc-hb04.sh
+++ b/configs/apps/xhc-hb04/xhc-hb04.sh
@@ -2,7 +2,7 @@
 
 thisfile=$(readlink -f "$0")
 thisdir=$(dirname "$thisfile")
-cd "$thisdir" || exit
+cd "$thisdir" || { echo "E: Could not change directory to '$thisdir'"; exit 1; }
 
 LAYOUT=${1:-""}
 

From 7439f102f5135623a051c03ed8c0dcd04d2d5716 Mon Sep 17 00:00:00 2001
From: Bertho Stultiens <bertho@vagrearg.org>
Date: Fri, 31 Jan 2025 12:33:14 +0100
Subject: [PATCH 3/4] Remove superfluous (noclobber) file truncate. File will
 be overwritten anyway.

---
 scripts/pyvcp_demo | 1 -
 1 file changed, 1 deletion(-)

diff --git a/scripts/pyvcp_demo b/scripts/pyvcp_demo
index 1fab35e347a..febb7295b24 100755
--- a/scripts/pyvcp_demo
+++ b/scripts/pyvcp_demo
@@ -108,7 +108,6 @@ done
 cd "$(dirname "$HALFILE")" || { echo "E: Could not change directory to '$(dirname "$HALFILE")'"; exit 1; }
 
 halmsg=/tmp/pyvcp_demo_halcmd.err
-true >| "$halmsg"
 halcmd -f "$HALFILE" > "$halmsg" 2>&1
 halstatus=$?
 if [ "$halstatus" != 0 ] ; then

From 2d257a1395c05818a1ed881f6f3885894dd4cca0 Mon Sep 17 00:00:00 2001
From: Bertho Stultiens <bertho@vagrearg.org>
Date: Sun, 2 Feb 2025 15:56:44 +0100
Subject: [PATCH 4/4] Redirect to file even if noclobber is set.

---
 scripts/pyvcp_demo | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/pyvcp_demo b/scripts/pyvcp_demo
index febb7295b24..5505914b615 100755
--- a/scripts/pyvcp_demo
+++ b/scripts/pyvcp_demo
@@ -108,7 +108,7 @@ done
 cd "$(dirname "$HALFILE")" || { echo "E: Could not change directory to '$(dirname "$HALFILE")'"; exit 1; }
 
 halmsg=/tmp/pyvcp_demo_halcmd.err
-halcmd -f "$HALFILE" > "$halmsg" 2>&1
+halcmd -f "$HALFILE" >| "$halmsg" 2>&1
 halstatus=$?
 if [ "$halstatus" != 0 ] ; then
   IFS=$'\n' # split lines