compare lists of comma separated options

[w5000]

hello,
I want to compare list of default shells with list of shells on a host (to get "missing" and superfluous shells configured on a host).
Below is my current solution in ksh script using arrays.
Do you see it could be done more efficient/easier with e.g. awk or the solution I paste is good enough?

$ cat ./test_arr
#!/bin/ksh

set -A stdshells $(echo $S1|sed s/\,/\ /g)
set -A hstshells $(echo $S2|sed s/\,/\ /g)

checkshells ()
{
for a in "${stdshells[@]}"; do
  if [[ " ${hstshells[*]} " != *" $a "* ]]; then
    printf "$a(-),"
  fi
done

for a in "${hstshells[@]}"; do
  if [[ " ${stdshells[*]} " != *" $a "* ]]; then
    printf "$a(+),"
  fi
done
}

checkshells | awk '{sub(/,$/,"");print}'

$ export S1=/bin/bsh,/bin/csh,/bin/false,/bin/ftponly
$ export S2=/bin/bsh,/bin/csh,/bin/extra,/bin/ftponly
$ ./test_arr
/bin/false(-),/bin/extra(+)
$ export S1=/bin/bsh,/bin/csh,/bin/false,/bin/ftponly,/bin/csh
$ ./test_arr
/bin/false(-),/bin/extra(+)
$ export S2=/bin/bsh,/bin/csh,/bin/extra,/bin/ftponly,/bin/csh,/bin/csh
$ ./test_arr
/bin/false(-),/bin/extra(+)
$ export S1=/bin/bsh,/bin/csh,/bin/false,/bin/ftponly,/bin/csh,/bin/csh2
$ ./test_arr
/bin/false(-),/bin/csh2(-),/bin/extra(+)
$ export S2=/bin/bsh,/bin/csh,/bin/extra,/bin/ftponly,/bin/csh,/bin/csh,EXTRA
$ ./test_arr
/bin/false(-),/bin/csh2(-),/bin/extra(+),EXTRA(+)
$

 

[Annihilannic]

Seems good enough, I would probably have sorted the two lists and used 'diff' and customised output format, or 'comm' and my own format handling, but I don't think it would be any better really. And yes, you could use perl/awk/whatever but it would just be the same code as you wrote in a different language...

Annihilannic
[small]tgmlify - code syntax highlighting for your tek-tips posts[/small]

 

[PHV]

Why using arrays ?

#!/bin/ksh
IFS=",$IFS"
checkshells() {
for a in $S1; do
  if [[ ",$S2," != *",$a,"* ]]; then
    printf "$a(-),"
  fi
done
for a in $S2; do
  if [[ ",$S1," != *",$a,"* ]]; then
    printf "$a(+),"
  fi
done
}
checkshells | awk '{sub(/,$/,"");print}'

Hope This Helps, PH.
FAQ219-2884
FAQ181-2886