In /usr/bin/debman line 40: ARGS=`getopt -l help,filename:,package: -o hf:p: -n debman -- "$@"` ^-- SC2006: Use $(...) notation instead of legacy backticked `...`. Did you mean: ARGS=$(getopt -l help,filename:,package: -o hf:p: -n debman -- "$@") In /usr/bin/debman line 70: if ( [ -n "$FILENAME" ] && [ -n "$PACKAGE" ] ) || \ ^-- SC2235: Use { ..; } instead of (..) to avoid subshell overhead. In /usr/bin/debman line 71: ( [ -z "$FILENAME" ] && [ -z "$PACKAGE" ] ); then ^-- SC2235: Use { ..; } instead of (..) to avoid subshell overhead. In /usr/bin/debman line 83: TEMPDIR=`mktemp -dt debman.XXXXXXXXXX` ^----------------------------^ SC2006: Use $(...) notation instead of legacy backticked `...`. Did you mean: TEMPDIR=$(mktemp -dt debman.XXXXXXXXXX) In /usr/bin/debman line 89: FILENAME="`find \"$TEMPDIR\" -name \*.deb -print`" ^-- SC2006: Use $(...) notation instead of legacy backticked `...`. Did you mean: FILENAME="$(find \"$TEMPDIR\" -name \*.deb -print)" In /usr/bin/debman line 101: (tar -C "$TEMPDIR" -xf - $MANDIRS 2>/dev/null || true) ^------^ SC2086: Double quote to prevent globbing and word splitting. Did you mean: (tar -C "$TEMPDIR" -xf - "$MANDIRS" 2>/dev/null || true) For more information: https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ... https://www.shellcheck.net/wiki/SC2006 -- Use $(...) notation instead of le... https://www.shellcheck.net/wiki/SC2235 -- Use { ..; } instead of (..) to av...