eval help


 
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# 1  
Old 11-04-2010
eval help

I am trying to expand the variable $user in my alias command and tried
several variations of eval but can't seem to get it to work.

The end result should be either:

oracle_user='sudo su - oracle ' or oracle_user='sudo su - oracle1 '


Code:
 
user=$(grep '^oracle:' /etc/passwd | cut -d":" -f1 )
if [ -z "$user" ]
  then
     user=$(grep '^oracle1:' /etc/passwd | cut -d":" -f1 )
     if [ -z "user" ]
     then
         echo "users oracle or oracle1 not found."
      fi
  fi

 
alias -x oracle_user='sudo su - $user '

Any help would be greatly appreciated
# 2  
Old 11-04-2010
Use double quotes
Code:
alias -x oracle_user="sudo su - $user "

# 3  
Old 11-04-2010
And the second test is missing a $ sign.
Code:
     if [ -z "$user" ]

# 4  
Old 11-04-2010
Code:
alias -x oracle_user='sudo su - $user'
 
alias oracle_user
oracle_user='sudo su - $user'

As mentioned above how come $user is not expanded to either oracle or oracle1

Last edited by vbe; 11-04-2010 at 01:37 PM.. Reason: corrected /code .. not backslash...
# 5  
Old 11-04-2010
The answer is in post #2 .
Variables between single quotes are not expanded. Variables between double quotes are expanded.
# 6  
Old 11-04-2010
thanks i missed the double quotes
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