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3

1

I want to create a script that change a username.
I want to check if the user is not a system user.
My idea is to check /etc/passwd and pick only users with an ID between 1000 and 60000 and users that have a /home directory like

 user:x:1005:1021::/home/user:/bin/sh

My grep command for now is like

 egrep -E '1[0-9]3.*/home' /etc/passwd 

As you can see, it doesn't match my [1000-60000] pattern nor the name

command-line

share|improve this question

asked 9 hours ago

danasodanaso

1822 bronze badges

New contributor

danaso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Minor point: grep -E is the same thing as egrep. There's no point in using both (egrep -E), just use grep -E.
  
  – terdon♦
  9 hours ago
  

  
  
  
  

add a comment | 

3

1

I want to create a script that change a username.
I want to check if the user is not a system user.
My idea is to check /etc/passwd and pick only users with an ID between 1000 and 60000 and users that have a /home directory like

 user:x:1005:1021::/home/user:/bin/sh

My grep command for now is like

 egrep -E '1[0-9]3.*/home' /etc/passwd 

As you can see, it doesn't match my [1000-60000] pattern nor the name

command-line

share|improve this question

asked 9 hours ago

danasodanaso

1822 bronze badges

New contributor

danaso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Minor point: grep -E is the same thing as egrep. There's no point in using both (egrep -E), just use grep -E.
  
  – terdon♦
  9 hours ago
  

  
  
  
  

add a comment | 

I want to create a script that change a username.
I want to check if the user is not a system user.
My idea is to check /etc/passwd and pick only users with an ID between 1000 and 60000 and users that have a /home directory like

 user:x:1005:1021::/home/user:/bin/sh

My grep command for now is like

 egrep -E '1[0-9]3.*/home' /etc/passwd 

As you can see, it doesn't match my [1000-60000] pattern nor the name

command-line

share|improve this question

asked 9 hours ago

danasodanaso

1822 bronze badges

New contributor

danaso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

 user:x:1005:1021::/home/user:/bin/sh

 egrep -E '1[0-9]3.*/home' /etc/passwd 

share|improve this question

asked 9 hours ago

danasodanaso

1822 bronze badges

New contributor

danaso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

share|improve this question

asked 9 hours ago

danasodanaso

1822 bronze badges

New contributor

danaso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

asked 9 hours ago

danasodanaso

1822 bronze badges

New contributor

danaso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

asked 9 hours ago

danasodanaso

1822 bronze badges

1 Answer
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7

You can use awk to find local users with id >= 1000:

awk -F: '$3>=1000 && $3!=65534 print $1' /etc/passwd

To also check for a home folder below /home:

awk -F: '$3>=1000 && $3 != 65534 && $6 ~ /^/home/ print $1' /etc/passwd

Replace /etc/passwd with <(getent passwd) to list all users including network accounts ...

See also this related question, as well as this one.

share|improve this answer

edited 9 hours ago

answered 9 hours ago

pLumopLumo

10k2121 silver badges4848 bronze badges

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks! but how can I merge all my patterns e.g name + ID + /home?
  
  – danaso
  9 hours ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  You're amazing! thanks!
  
  – danaso
  9 hours ago
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  Mind that this does not list LDAP users so is only useable for local users :)
  
  – Rinzwind
  9 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks @Rinzwind. I didn't know
  
  – danaso
  9 hours ago
  

  
  
  
  

add a comment | 

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7

You can use awk to find local users with id >= 1000:

awk -F: '$3>=1000 && $3!=65534 print $1' /etc/passwd

To also check for a home folder below /home:

awk -F: '$3>=1000 && $3 != 65534 && $6 ~ /^/home/ print $1' /etc/passwd

Replace /etc/passwd with <(getent passwd) to list all users including network accounts ...

See also this related question, as well as this one.

share|improve this answer

edited 9 hours ago

answered 9 hours ago

pLumopLumo

10k2121 silver badges4848 bronze badges

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks! but how can I merge all my patterns e.g name + ID + /home?
  
  – danaso
  9 hours ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  You're amazing! thanks!
  
  – danaso
  9 hours ago
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  Mind that this does not list LDAP users so is only useable for local users :)
  
  – Rinzwind
  9 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks @Rinzwind. I didn't know
  
  – danaso
  9 hours ago
  

  
  
  
  

add a comment | 

7

You can use awk to find local users with id >= 1000:

awk -F: '$3>=1000 && $3!=65534 print $1' /etc/passwd

To also check for a home folder below /home:

awk -F: '$3>=1000 && $3 != 65534 && $6 ~ /^/home/ print $1' /etc/passwd

Replace /etc/passwd with <(getent passwd) to list all users including network accounts ...

See also this related question, as well as this one.

share|improve this answer

edited 9 hours ago

answered 9 hours ago

pLumopLumo

10k2121 silver badges4848 bronze badges

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks! but how can I merge all my patterns e.g name + ID + /home?
  
  – danaso
  9 hours ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  You're amazing! thanks!
  
  – danaso
  9 hours ago
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  Mind that this does not list LDAP users so is only useable for local users :)
  
  – Rinzwind
  9 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks @Rinzwind. I didn't know
  
  – danaso
  9 hours ago
  

  
  
  
  

add a comment | 

You can use awk to find local users with id >= 1000:

awk -F: '$3>=1000 && $3!=65534 print $1' /etc/passwd

To also check for a home folder below /home:

awk -F: '$3>=1000 && $3 != 65534 && $6 ~ /^/home/ print $1' /etc/passwd

Replace /etc/passwd with <(getent passwd) to list all users including network accounts ...

See also this related question, as well as this one.

share|improve this answer

edited 9 hours ago

answered 9 hours ago

pLumopLumo

10k2121 silver badges4848 bronze badges

awk -F: '$3>=1000 && $3!=65534 print $1' /etc/passwd

awk -F: '$3>=1000 && $3 != 65534 && $6 ~ /^/home/ print $1' /etc/passwd

share|improve this answer

edited 9 hours ago

answered 9 hours ago

pLumopLumo

10k2121 silver badges4848 bronze badges

answered 9 hours ago

pLumopLumo

10k2121 silver badges4848 bronze badges

answered 9 hours ago

pLumopLumo

10k2121 silver badges4848 bronze badges