In /usr/bin/cgns_unitconv line 5:
dir=`dirname $0`
    ^----------^ SC2006: Use $(...) notation instead of legacy backticked `...`.
             ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
dir=$(dirname "$0")


In /usr/bin/cgns_unitconv line 9:
. /usr/share/cgnstools/cgconfig
  ^---------------------------^ SC1091: Not following: /usr/share/cgnstools/cgconfig was not specified as input (see shellcheck -x).


In /usr/bin/cgns_unitconv line 17:
   if test -x $d/calcwish ; then
              ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
   if test -x "$d"/calcwish ; then


In /usr/bin/cgns_unitconv line 21:
  if test -x $d/cgnswish/calcwish ; then
             ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
  if test -x "$d"/cgnswish/calcwish ; then


In /usr/bin/cgns_unitconv line 36:
  if test -f $d/unitconv.tcl ; then
             ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
  if test -f "$d"/unitconv.tcl ; then


In /usr/bin/cgns_unitconv line 56:
exec $calcwish $unitconv
     ^-------^ SC2086: Double quote to prevent globbing and word splitting.
               ^-------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
exec "$calcwish" "$unitconv"

For more information:
  https://www.shellcheck.net/wiki/SC1091 -- Not following: /usr/share/cgnstoo...
  https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...
  https://www.shellcheck.net/wiki/SC2006 -- Use $(...) notation instead of le...