help please!!!!

Shell Programming and Scripting
1

how do you get the file permissions to strings
like rwx------ read,write,executable to users

2

Rather than going for a script, see if the command aclget solves your purpose.

man aclget
3

check if this is what you want:

stat -c '%A' filename

or

stat -c '%a' filename
4

Can the result from this be used as a variable..I mean if a file has following permissions
rwxr-xr--
I want the output to be:
this file has the following permissions:-
Read, Write and Execute for the user.
Read and Execute for the group.
Read only for the others.

Is it possible?

5

maybe something like :-

filename=$1
uperms=`ls -l $filename|cut -c2-4`
gperms=`ls -l $filename|cut -c5-7`
operms=`ls -l $filename|cut -c8-10`

then you can case for the responses you want or whatever.

6

Or even just run the command once.

perms=`ls -l "$1" | cut -f1`
case $perms in
  ?r?????????) echo Read for owner;;
esac
case $perms in
 ??w???????) echo Write for owner;;
esac

etcetera. For maintainability, it would be better to loop over user, group, and other, and only case on the first three characters of the value.

perms=${perms#?}
for role in user group other; do
  case $perms in
    r??*) echo read for $role;;
  esac
  case $perms in
    ?w?*) echo write for $role;;
  esac
  case $perms in
    ??x*) echo execute for $role;;
  esac
  perms=${perms#???}
done
1 Like
7

thanx a lot era and repudi8or..but i ve got a problem in case..
will i be able to get to conditions in one line..
like if a file has rx for the group
i want to have the out put to be read, execute to the user

i know when you put in the case
r?x) echo read execute to the user
will do but it also gives the individual out puts..how do you stop that ???

8

You can collect them into a single string instead of printing one line for each.

perms=`ls -l "$1" | cut -f1`
perms=${perms#?}
for role in user group other; do
  what=none
  case $perms in
    r??*) what=read;;
  esac
  case $perms in
    ?w?*) what="$what"${what:+", "}"write";;
  esac
  case $perms in
    ??x*) what="$what"${what:+", "}"execute";;
  esac
  echo "$what for $role"
  perms=${perms#???}
done

The construct ${variable:+something} means "if variable is empty, substitute nothing; otherwise, substitute 'something'". Your shell might be picky about how much quoting it tolerates in this construct; play around with different quoting if you can't get this to work directly (or simply give up on having commas between the values, as a crude workaround).