Shell Programming and Scripting

 $ ruby -e 'a=File.read("file").split; a.permutation(a.length).to_a.each {|x| puts x.join}'

paste -sd " " file | awk '{split($0,a," ")}END{
for(i=1;i<=NF;i++) {printf $i;for(j=2;j<=NF;j++) {printf "+"a[j]}print "="}
}'
1+2+3+4+5=
2+2+3+4+5=
3+2+3+4+5=
4+2+3+4+5=
5+2+3+4+5=

#!/bin/ksh
function perm {
  typeset p=$1 s=$2 i
  for i in "${NR[@]}"
  do
    if [ $p -eq 1 ]; then
      printf "%s%s=\n" "$s" "$i"
    else
      perm $((p-1)) "$s$i+"
    fi
  done
}

while read nr; do
  NR[$((i++))]=$nr
done < infile
perm ${#NR[@]}

awk 'function perm(p,s,     i) {
       for(i=1;i<=n;i++)
         if(p==1)
           printf "%s%s=\n",s,A[i]
         else
           perm(p-1,s A[i]"+")
     }
     {
       A[++n]=$1
     }
     END{
       perm(n)
     }' infile