#ash# set +o posix#ash# declare -i iv jvecho "Format: 'expected actual'"iv=$(( 3 + 5 * 32 ))echo 163 $iv#ash# iv=iv+3#ash# echo 166 $iviv=2jv=ivlet "jv *= 2"echo 4 $jvjv=$(( $jv << 2 ))echo 16 $jvlet jv="$jv / 2"echo 8 $jv#ash# jv="jv >> 2"      let jv="jv >> 2"echo 2 $jviv=$((iv+ $jv))echo 4 $ivecho 2 $((iv -= jv))echo 2 $ivecho 1 $(( iv == jv ))echo 0 $(( iv != $jv ))echo 0 $(( iv < jv ))echo 0 $(( $iv > $jv ))echo 1 $(( iv <= $jv ))echo 1 $(( $iv >= jv ))echo 2 $jvecho -3 $(( ~$jv ))echo -2 $(( ~1 ))echo 1 $(( ! 0 ))echo 0 $(( jv % 2 ))echo 2 $(( $iv % 4 ))echo 131072 $(( iv <<= 16 ))echo 29 $(( iv %= 33 ))echo 33 $(( 33 & 55 ))echo 49 $(( 33 | 17 ))echo 1 $(( iv && $jv ))echo 1 $(( $iv || jv ))echo 0 $(( iv && 0 ))echo 0 $(( iv & 0 ))echo 1 $(( iv && 1 ))echo 1 $(( iv & 1 ))echo 1 $(( $jv || 0 ))echo 2 $(( jv | 0 ))echo 3 $(( jv | 1 ))echo 1 $(( $jv || 1 ))let 'iv *= jv'echo 58 $ivecho 2 $jvlet "jv += $iv"echo 60 $jvecho 1 $(( jv /= iv ))echo 256 $(( jv <<= 8 ))echo 16 $(( jv >>= 4 ))echo 62 $(( iv |= 4 ))echo 4 $(( iv &= 4 ))echo 29 $(( iv += (jv + 9)))echo 5 $(( (iv + 4) % 7 ))# unary plus, minusecho -4 $(( +4 - 8 ))echo 4 $(( -4 + 8 ))# conditional expressionsecho 1 $(( 4<5 ? 1 : 32))echo 32 $(( 4>5 ? 1 : 32))echo 32 $(( 4>(2+3) ? 1 : 32))echo 1 $(( 4<(2+3) ? 1 : 32))echo 1 $(( (2+2)<(2+3) ? 1 : 32))echo 32 $(( (2+2)>(2+3) ? 1 : 32))# check that the unevaluated part of the ternary operator does not do# evaluation or assignmentx=i+=2y=j+=2#ash# declare -i i=1 j=1      i=1      j=1echo 20 $((1 ? 20 : (x+=2)))#ash# echo $i,$x             # ash mishandles thisecho 30 $((0 ? (y+=2) : 30))#ash# echo $j,$y             # ash mishandles thisx=i+=2y=j+=2#ash# declare -i i=1 j=1      i=1      j=1echo 20 $((1 ? 20 : (x+=2)))#ash# echo $i,$x             # ash mishandles thisecho 30 $((0 ? (y+=2) : 30))#ash# echo $i,$y             # ash mishandles this# check precedence of assignment vs. conditional operator# should be an error#ash# declare -i x=2      x=2#ashnote# bash reports error but continues, ash aborts - using subshell to 'emulate' bash:(  y=$((1 ? 20 : x+=2))  )# check precedence of assignment vs. conditional operator#ash# declare -i x=2      x=2# ash says "line NNN: syntax error: 0 ? x+=2 : 20"#ash# echo 20 $((0 ? x+=2 : 20))# associativity of assignment-operator operator#ash# declare -i i=1 j=2 k=3i=1j=2k=3echo 6 $((i += j += k))echo 6,5,3 $i,$j,$k# octal, hexecho 263 $(( 0x100 | 007 ))echo 255 $(( 0xff ))#ash# echo 255 $(( 16#ff ))#ash# echo 127 $(( 16#FF/2 ))#ash# echo 36 $(( 8#44 ))echo 40 $(( 8 ^ 32 ))#ash# # other bases#ash# echo 10 $(( 16#a ))#ash# echo 10 $(( 32#a ))#ash# echo 10 $(( 56#a ))#ash# echo 10 $(( 64#a ))#ash##ash# echo 10 $(( 16#A ))#ash# echo 10 $(( 32#A ))#ash# echo 36 $(( 56#A ))#ash# echo 36 $(( 64#A ))#ash##ash# echo 62 $(( 64#@ ))#ash# echo 63 $(( 64#_ ))#ash# # weird bases (error)#ash# echo $(( 3425#56 ))#ash# # missing number after base#ash# echo 0 $(( 2# ))# these should generate errors(  echo $(( 7 = 43 ))      )#ash# echo $(( 2#44 ))(  echo $(( 44 / 0 ))      )(  let 'jv += $iv'         )(  echo $(( jv += \$iv ))  )(  let 'rv = 7 + (43 * 6'  )#ash# # more errors#ash# declare -i i#ash# i=0#4#ash# i=2#110#11((echo abc; echo def;); echo ghi)#ash# if (((4+4) + (4 + 7))); then#ash# 	echo ok#ash# fi#ash# (())	# make sure the null expression works OK#ash# a=(0 2 4 6)#ash# echo 6 $(( a[1] + a[2] ))#ash# echo 1 $(( (a[1] + a[2]) == a[3] ))#ash# (( (a[1] + a[2]) == a[3] )) ; echo 0 $?# test pushing and popping the expression stackunset AA="4 + "(  echo A $(( ( 4 + A ) + 4 ))  )A="3 + 5"echo 16 $(( ( 4 + A ) + 4 ))# badly-formed conditional expressions(  echo $(( 4 ? : $A ))  )(  echo $(( 1 ? 20 ))    )(  echo $(( 4 ? 20 : ))  )# precedence and short-circuit evaluationB=9echo 9 $B# error(  echo $(( 0 && B=42 )); echo 9 $B  )# error(  echo $(( 1 || B=88 )); echo 9 $B  )# ash mistakenly evaluates B=... below#ash# echo 0 $(( 0 && (B=42) ))echo 9 $B#ash# echo 0 $(( (${$} - $$) && (B=42) ))echo 9 $B#ash# echo 1 $(( 1 || (B=88) ))echo 9 $B# until command with (( )) commandx=7echo 7 $x#ash# until (( x == 4 ))      until test "$x" = 4do	echo $x	x=4doneecho 4 $x# exponentiationecho 32767 $(( 2**15 - 1))echo 32768 $(( 2**(16-1)))echo 131072 $(( 2**16*2 ))echo 2147483647 $(( 2**31-1))echo 1 $(( 2**0 ))# {pre,post}-{inc,dec}rement and associated errorsx=4echo 4 $xecho 4 $(( x++ ))echo 5 $xecho 5 $(( x-- ))echo 4 $xecho 3 $(( --x ))echo 3 $xecho 4 $(( ++x ))echo 4 $x# bash 3.2 apparently thinks that ++7 is 7#ash# echo 7 $(( ++7 ))(  echo $(( 7-- ))    )(  echo $(( --x=7 ))  )(  echo $(( ++x=7 ))  )(  echo $(( x++=7 ))  )(  echo $(( x--=7 ))  )echo 4 $xecho 7 $(( +7 ))echo -7 $(( -7 ))# bash 3.2 apparently thinks that ++7 is 7#ash# echo $(( ++7 ))#ash# echo $(( --7 ))${THIS_SH} ./arith1.sub${THIS_SH} ./arith2.subx=4y=7#ash# (( x=8 , y=12 ))      x=8      y=12echo $x $y#ash# # should be an error#ash# (( x=9 y=41 ))# These are errorsunset b(  echo $((a b))  )#ash# ((a b))n=42printf "%d\n" $nprintf "%i\n" $n#ash# echo $(( 8#$(printf "%o\n" $n) ))printf "%u\n" $n#ash# echo $(( 16#$(printf "%x\n" $n) ))#ash# echo $(( 16#$(printf "%X\n" $n) ))# causes longjmp botches through bash-2.05ba[b[c]d]=e