This is the mail archive of the cygwin@cygwin.com mailing list for the Cygwin project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: suggestion for cygutils - usermod (was Re: howto change home path in /etc/passwd)


On Mon, 12 May 2003 Sylvain.Ferriol@imag.fr wrote:

> Surlignage Igor Pechtchanski <pechtcha@cs.nyu.edu>:
>
> > On Mon, 12 May 2003 Sylvain.Ferriol@imag.fr wrote:
> >
> > > Surlignage Max Bowsher <maxb@ukf.net>:
> > >
> > > > Sylvain.Ferriol@imag.fr wrote:
> > > > > Yes , because i don't want to create a shell doing this:
> > > > > grep -v $USERNAME /etc/passwd > /etc/passwd
> > > >
> > > sorry
> > > but i don't know with sed how to delete a line starting with $USER
> >
> > For the record: "sed '/'$USER':/d".  However, grep is perfectly adequate.
> > What Max was warning you about was the shell redirection mechanism.  You'd
> > be safer using something like
> >
> >   cp -p /etc/passwd /etc/passwd-bak-tmp && grep -v $USERNAME
> > /etc/passwd-bak-tmp > /etc/passwd && rm -f /etc/passwd-bak-tmp
> >
> is it better to use $USER or $USERNAME??
>
> sylvain

$USERNAME is set by Windows.  $USER is set by /etc/profile to the output
of "id -un".  They should be the same in most cases (they even seem to be
the same if "login" is used to switch user contexts from a SYSTEM-owned
shell -- go figure).  Which would be better depends on the purpose, I
guess...
	Igor

> > > > Care! That will leave you with an empty /etc/passwd.
> > > > The shell truncates /etc/passwd BEFORE grep reads it.
> > > >
> > > > > mkpasswd -l -u $USERNAME -p $HOME >> /etc/passwd
> > > >
> > > > Max.

-- 
				http://cs.nyu.edu/~pechtcha/
      |\      _,,,---,,_		pechtcha@cs.nyu.edu
ZZZzz /,`.-'`'    -.  ;-;;,_		igor@watson.ibm.com
     |,4-  ) )-,_. ,\ (  `'-'		Igor Pechtchanski
    '---''(_/--'  `-'\_) fL	a.k.a JaguaR-R-R-r-r-r-.-.-.  Meow!

Knowledge is an unending adventure at the edge of uncertainty.
  -- Leto II


--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]