Bash 101 Help Please

[Matt Graham]

From: Lisa Kachold 
> createNewSambaAllow(){
>         # Copy to backup the config:
>          cp /etc/samba/smb.conf /etc/samba/smb.conf-$_now
> # stuff the line we need to append to into a variable called $oldline
> # this is supposed to look like this "valid users = unique thing1 thing2
thing3 alice"
>         oldline = grep unique /etc/samba/smb.conf*
>         # delete the old line in the smb.conf*
>         sed '/unique/d' /etc/samba/smb.conf >>/etc/samba/smb.conf
>         # dump the old line and the new user into the bottom of smb.conf
>         echo $oldline && echo $username  >> /etc/samba/smb.conf
>         # restart samba
>        /etc/init.d/samba restart
>         echo "Samba Config Added and Daemon restarted"
> }
[snip]
>         createNewSambaAllow $username
[more snip]

What I *think* you want this thing to do is to replace the line containing
"unique" with a new line that has " $username" appended to it.  There are many
ways to do this.  The function above won't work, or at least it didn't when I
tested it.  This, OTOH:

createNewSambaAllow(){
        # Copy to backup the config:
        cp /etc/samba/smb.conf /etc/samba/smb.conf-$_now
        # stuff the line we need to append to into a variable called $oldline
        # this is supposed to look like this "valid users = unique thing1
thing2 thing3 alice"
        old=`grep unique /etc/samba/smb.conf`
        # delete the old line in the smb.conf
        sed "/unique/d" /etc/samba/smb.conf > temp.txt
        # dump the old line and the new user into the bottom of smb.conf
        old=`echo $old | sed -e "s/$/ $1/"`
        echo $old  >> temp.txt
        mv -f temp.txt /etc/samba/smb.conf
        # restart samba
        #/etc/init.d/samba restart
        echo "Samba Config Added and Daemon restarted"
}
# end function

This appears to do what you want while retaining the structure, but using sed
in place should also work and make the function collapse into a single line:

sed -e "s/\(.*valid users.*\)/\1 $username/" -i /etc/samba/smb.conf

...which would probably be a win.

This might've been easier to do in Perl, but then most things are :-)

-- 
Matt G / Dances With Crows
The Crow202 Blog:  http://crow202.org/wordpress/
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