Shell Programming and Scripting

abc.txt  -rw-r--r--

stat -c "%a" file

#!/bin/bash
#
# getperm
 
for i in $(ls -ld ${1} | awk 'BEGIN{FIELDWIDTHS="4 3 3"}{print $1,$2,$3}'); do
    ((++j))
    while read -n 1 bit; do
          [[ x${bit} == x ]] && break
          case ${bit} in
          s|S) ((tib=j==1?4:2)) && ((mus+=tib))
               [[ ${bit} == s ]] && bit=1 || bit=0 ;;
          t|T) ((++mus)) 
               [[ ${bit} == t ]] && bit=1 || bit=0 ;;
          r)   bit=4 ;;
          w)   bit=2 ;;
          x)   bit=1 ;;
          *)   bit=0 ;;
          esac 
          ((sum+=bit))
    done < <(echo ${i})
    perm+="${sum}" && sum=
done 
[[ x${mus} == x ]] && mus=0
echo ${mus}${perm}

awk 'BEGIN{FIELDWIDTHS="4 3 3"}{print $1,$2,$3}'

sed 's/\(....\)\(...\)\(...\)\(.*\)/\1 \2 \3/g'

bash getperm.sh file

 
perl -e 'for (@ARGV) { printf "%04o %s",  (stat)[2] & 07777, $_ }' file_name

PERMS=$(ls -ald abc.txt|cut -f1 -d" ")
if [ "${PERMS}" = "-rw-r--r--" ]
then
        ls -ald abc.txt
        chmod 666 abc.txt
        ls -lad abc.txt
fi

find . -perm 644 | xargs -iFile chmod 666 File

if [ -f "/full_path_to_file/abc.txt" ]
then
           find "/full_path_to_file/abc.txt" -perm 0644 -exec chmod 666 {} \;
fi