6

I am writing a program to disable users from a system, i want to replace /bin/bash to /bin/false.

Example 

xxx:x:1:22:xx:/export/home/xx:**/bin/bash**

replace to

xxx:x:1:22:xx:/export/home/xx:**/bin/false**

I want do with using bash script.

I know one way to do this is using sed. But i am not good at regular expressions.

Can any one help?

2 Answers2

9

Well you don't do it at all with sed or regular expressions. What you do is to use the program chsh to change the shell of a user.

chsh -s /bin/false username

alternatively:

usermod -s /bin/false username

If you wanted to replace it with an actual shell you'd also have to make sure that it is listed in /etc/shells.

0xC0000022L
  • 7,544
  • 10
  • 54
  • 94
5

Please be aware that chsh is not always available! in alpine Linux for example or embeded systems using busybox ..

Simple inline sed command :

sed -i '/www-data/s/false/sh/g' /etc/passwd

(This example changes shell from /bin/false to /bin/sh for user www-data )

Pooya
  • 161