[ILUG] Usernames starting with numbers?

[Brian Foster]

  | Date: Thu, 6 Jun 2002 21:38:43 +0100
  | From: Robert Synnott <r.synnott at oceanfree.net>
  | 
  |[ ... ]  Tools like 'useradd' etc. say that usernames starting
  | in numbers are invalid, as are unsernames containing appostrophies.
  | However, when added to /etc/passwd manually, these seem to work fine,
  | as long as the home directory, which is just a  mount point anyway in
  | this case, is a valid name.  Can doing this cause any problems?

 possibly.  utilities which accept usernames as arguments/input
 also usually accept UIDs as well.  a username which starts with
 digits "looks like" a number, i.e., a UID, to at least some of
 those utilities (at least historically), and hence use what is
 quite probably the wrong value, and do the wrong thing.¹

 I've no idea what the issue is with an apostrophe?  whilst it's
 a shell meta-character (a quoting convention), that doesn't seem
 (to me) a sufficiently strong justification to dis-recommending
 it's use ....   OTOH, the quality of some shell scripts is so
 poor that maybe it is a sufficient rationale?

cheers!
	-blf-

 ¹ people should really learn to use strtol(3) and friends, and
   learn to use them _properly_, so this sort of problem is less
   like to happen.  (read: "avoid atoi(3) &tc")   grrr.....
--
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