In /usr/bin/fsbench line 10:
    if [ ! $? -eq 0 ]; then
           ^-- SC2181: Check exit code directly with e.g. 'if mycmd;', not indirectly with $?.


In /usr/bin/fsbench line 32:
    if ! expr $num + 0 >/dev/null 2>&1; then
         ^--^ SC2003: expr is antiquated. Consider rewriting this using $((..)), ${} or [[ ]].
              ^--^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    if ! expr "$num" + 0 >/dev/null 2>&1; then


In /usr/bin/fsbench line 39:
freemb=`df -m . | tail -1 | awk '{print $4}'`
       ^-- SC2006: Use $(...) notation instead of legacy backticked `...`.

Did you mean: 
freemb=$(df -m . | tail -1 | awk '{print $4}')


In /usr/bin/fsbench line 40:
if [ $num -gt $freemb ]; then
     ^--^ SC2086: Double quote to prevent globbing and word splitting.
              ^-----^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
if [ "$num" -gt "$freemb" ]; then


In /usr/bin/fsbench line 41:
    echo $num MB diskspace needed, but only $freemb MB found.
         ^--^ SC2086: Double quote to prevent globbing and word splitting.
                                            ^-----^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    echo "$num" MB diskspace needed, but only "$freemb" MB found.


In /usr/bin/fsbench line 46:
for a in `seq -f "%04.0f" 1 $num`; do
         ^----------------------^ SC2006: Use $(...) notation instead of legacy backticked `...`.
                            ^--^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
for a in $(seq -f "%04.0f" 1 "$num"); do


In /usr/bin/fsbench line 47:
    totalmb=`echo ${totalmb}+${a}|bc`
            ^-----------------------^ SC2006: Use $(...) notation instead of legacy backticked `...`.
                             ^--^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    totalmb=$(echo ${totalmb}+"${a}"|bc)


In /usr/bin/fsbench line 50:
if [ `uname` = Linux ]; then
     ^-----^ SC2046: Quote this to prevent word splitting.
     ^-----^ SC2006: Use $(...) notation instead of legacy backticked `...`.

Did you mean: 
if [ $(uname) = Linux ]; then


In /usr/bin/fsbench line 51:
    if [ 0 -eq `id -u` ]; then
               ^-----^ SC2046: Quote this to prevent word splitting.
               ^-----^ SC2006: Use $(...) notation instead of legacy backticked `...`.

Did you mean: 
    if [ 0 -eq $(id -u) ]; then


In /usr/bin/fsbench line 52:
	echo "Filesystem:" `file -bLs $(df -h . | tail -1 | awk '{print $1}')`
                           ^-- SC2046: Quote this to prevent word splitting.
                           ^-- SC2006: Use $(...) notation instead of legacy backticked `...`.
                                      ^-- SC2046: Quote this to prevent word splitting.

Did you mean: 
	echo "Filesystem:" $(file -bLs $(df -h . | tail -1 | awk '{print $1}'))


In /usr/bin/fsbench line 57:
start=`date +%s.%N`
      ^-----------^ SC2006: Use $(...) notation instead of legacy backticked `...`.

Did you mean: 
start=$(date +%s.%N)


In /usr/bin/fsbench line 63:
if [ ! $? -eq 0 ]; then
       ^-- SC2181: Check exit code directly with e.g. 'if mycmd;', not indirectly with $?.


In /usr/bin/fsbench line 68:
for a in `seq -f "%04.0f" 1 $num | shuf`; do
         ^-----------------------------^ SC2006: Use $(...) notation instead of legacy backticked `...`.
                            ^--^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
for a in $(seq -f "%04.0f" 1 "$num" | shuf); do


In /usr/bin/fsbench line 69:
    percent=`echo ${mb}*100/${totalmb}|bc`
            ^----------------------------^ SC2006: Use $(...) notation instead of legacy backticked `...`.
                            ^--------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    percent=$(echo ${mb}*100/"${totalmb}"|bc)


In /usr/bin/fsbench line 70:
    mb=`echo ${mb}+${a}|bc`
       ^------------------^ SC2006: Use $(...) notation instead of legacy backticked `...`.
                   ^--^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    mb=$(echo ${mb}+"${a}"|bc)


In /usr/bin/fsbench line 72:
    dd if=/dev/zero of=_fsbench/$a bs=${a}M count=1 2>/dev/null
                                ^-- SC2086: Double quote to prevent globbing and word splitting.
                                      ^--^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    dd if=/dev/zero of=_fsbench/"$a" bs="${a}"M count=1 2>/dev/null


In /usr/bin/fsbench line 73:
    rm _fsbench/$a
                ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    rm _fsbench/"$a"


In /usr/bin/fsbench line 74:
    mkdir _fsbench/$a
                   ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    mkdir _fsbench/"$a"


In /usr/bin/fsbench line 81:
end=`date +%s.%N`
    ^-----------^ SC2006: Use $(...) notation instead of legacy backticked `...`.

Did you mean: 
end=$(date +%s.%N)


In /usr/bin/fsbench line 86:
t=`echo $end - $start | bc`
  ^-----------------------^ SC2006: Use $(...) notation instead of legacy backticked `...`.
        ^--^ SC2086: Double quote to prevent globbing and word splitting.
               ^----^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
t=$(echo "$end" - "$start" | bc)


In /usr/bin/fsbench line 87:
ts=`echo ${totalmb}/${t}|bc`
   ^-----------------------^ SC2006: Use $(...) notation instead of legacy backticked `...`.
         ^--------^ SC2086: Double quote to prevent globbing and word splitting.
                    ^--^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
ts=$(echo "${totalmb}"/"${t}"|bc)


In /usr/bin/fsbench line 88:
echo $t
     ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
echo "$t"

For more information:
  https://www.shellcheck.net/wiki/SC2046 -- Quote this to prevent word splitt...
  https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...
  https://www.shellcheck.net/wiki/SC2003 -- expr is antiquated. Consider rewr...