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Old 04-08-2010, 09:58 PM   #1
TheNewVegas
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Registered: Feb 2010
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How to get invalid user input into a variable


hey guys,

I have a script in which it searches the password file for a username based on the user's input. Is there a way I can take the bad input and keep it in a variable. (one that keeps adding all the non-existent users)

this is what I have so far

echo -n "Enter username: "
read username

grep -i "$username" /etc/passwd || echo "User not found."


so how would I get non-existent users into another variable?

thanks a lot!
Vegas
 
Old 04-08-2010, 10:32 PM   #2
chrism01
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Registered: Aug 2004
Location: Sydney
Distribution: Centos 6.8, Centos 5.10
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If I understand what you want
Code:
#straight copy (overwrite)
no_exist=$username

# concatenate
no_exist=$no_exist" "$username
 
Old 04-08-2010, 10:45 PM   #3
TheNewVegas
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Hey thanks for the response


Im trying to have the user enter a username they want to see the line in the password file that belongs to that user, but also keep the users that dont exist( that the user types in, into another variable) so that at the end of the script i can display all the names that are not accounts

I hope that makes sense
 
Old 04-08-2010, 10:45 PM   #4
TheNewVegas
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Hey thanks for the response


Im trying to have the user enter a username they want to see the line in the password file that belongs to that user, but also keep the users that dont exist( that the user types in, into another variable) so that at the end of the script i can display all the names that are not accounts

I hope that makes sense
 
Old 04-08-2010, 10:49 PM   #5
chrism01
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My 2nd suggestion is what you want if you want to loop asking the user for names until they give up.
 
Old 04-08-2010, 10:58 PM   #6
TheNewVegas
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would you be able to add that to what i have already? Im sorry, Im not sure what you mean.


at the end of the script i want to be able to show the variable with all the non-existent usernames.
something like "These are all the names you tried without accounts: bob rob ted fred alex jim"
 
Old 04-08-2010, 11:40 PM   #7
bakdong
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This could be improved:


username="1"; while [ ! -z $username ] ;do read -p "Enter username: " username; [ ! -z $username ] && grep -i "$username" /etc/passwd || echo "User not found."; notfound=`echo "$notfound" "$username"`;done;echo "These names not found: $notfound";
 
Old 04-09-2010, 12:21 AM   #8
TheNewVegas
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PERFECT


thanks alot!
 
Old 04-09-2010, 01:21 AM   #9
grail
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Don't forget to mark as SOLVED once you have your solution.
 
Old 04-09-2010, 03:43 AM   #10
bakdong
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Quote:
Originally Posted by TheNewVegas View Post
PERFECT


thanks alot!
He he... You're welcome. Definitely not perfect, but by all means use it to build on.
 
  


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