add user with name.name

Amr Ebeid · 03-26-2006, 03:30 AM

hi all
i'm a new user ti linux
how can i add a user the format of (user.familyname)

gilead · 03-26-2006, 03:40 AM

On my system (Slackware) you can't create a login name like that, the '.' is an illegal character. However, when you create a user you also add extra information, including a comment field that usually contains the user name. You can put whatever you like in that field. Have you had a look at man useradd

Ph0en1x · 03-27-2006, 05:18 PM

You might consider using an underscore. (user_familyname)

XavierP · 04-01-2006, 05:15 PM

Moved: This thread is more suitable in Linux-Newbie and has been moved accordingly to help your thread/question get the exposure it deserves.

reddazz · 04-01-2006, 05:42 PM

Useradd will let you create usernames with dots regardless of distro. Some other tools may not permit you to do this. You would need to do something like

Code:

#useradd -m firstname.surname

gilead · 04-01-2006, 05:52 PM

Are you sure about "regardless of distro"? Here's the output on Slackware:

Code:

# useradd joseph.blogs
useradd: invalid user name 'joseph.blogs'
# useradd -m joseph.blogs
useradd: invalid user name 'joseph.blogs'

reddazz · 04-01-2006, 06:08 PM

Quote:

Originally Posted by gilead

Are you sure about "regardless of distro"? Here's the output on Slackware:

Code:

# useradd joseph.blogs
useradd: invalid user name 'joseph.blogs'
# useradd -m joseph.blogs
useradd: invalid user name 'joseph.blogs'

I've just tried it on Gentoo, Suse, CentOS and Debian. It works fine on those distros but I get the same error as you on Arch. It leaves me wondering whether the other distros patch useradd to enable it to accept usernames with dots.

gilead · 04-01-2006, 06:14 PM

Quote:

Originally Posted by reddazz

It leaves me wondering whether the other distros patch useradd to enable it to accept usernames with dots.

I'd say you're right - in the shadow sources at http://cvsweb.pld.org.pl/shadow/libm...ame.c?rev=1.11, the user name must match [a-z_][a-z0-9_-]*[$] according to:

Code:

static int good_name (const char *name)
{
	/*
	 * User/group names must match [a-z_][a-z0-9_-]*[$]
	 */
	if (!*name || !((*name >= 'a' && *name <= 'z') || *name == '_'))
		return 0;

	while (*++name) {
		if (!((*name >= 'a' && *name <= 'z') ||
		      (*name >= '0' && *name <= '9') ||
		      *name == '_' || *name == '-' ||
		      (*name == '$' && *(name + 1) == '\0')))
			return 0;
	}

	return 1;
}

reddazz · 04-01-2006, 06:23 PM

One thing to note though is that if have a username with a dot, you cannot use chown or chgrp using dots because they will fail or cause problems. The code below would fail,

Code:

#chown firstname.surname.somegroup somefile

The right syntax would have to be,

Code:

#chown firstname.surname:somegroup somefile

Mitio · 11-29-2009, 08:35 AM

Today i have the same problem with my OS - FC12.
I need to create user: FNAME.LNAME, and when i tried (with and without-m) i received:

useradd: invalid user name

In comparison, in FC11 i haven't such problem.

The workaround i used is to create user manually:
1. create home directory:

Code:

# mkdir /home/FNAME.LNAME

2. adding user TEMPLATEUSER:

Code:

# useradd TEMPLATEUSER

3. change /etc/passwd:

Code:

 # cat /etc/passwd | sed -e "s/TEMPLATEUSER/FNAME.LNAME/g" > /etc/passwd

4. change /etc/group:

Code:

# cat /etc/group | sed -e "s/TEMPLATEUSER/FNAME.LNAME/g" > /etc/group

5. change /etc/shadow:

Code:

# cat /etc/shadow | sed -e "s/TEMPLATEUSER/FNAME.LNAME/g" > /etc/shadow

6. change permition to home directory:

Code:

# chown -R FNAME.LNAME:FNAME.LNAME /home/FNAME.LNAME

Please note, that this is workaround, and you could have problems with script that relay that you haven't dots in your username.