[vtysh] Never skip authentication, and add support for multiple -c commands

[vtysh] Never skip authentication, and add support for multiple -c commands

2006-07-27 Andrew J. Schorr <ajschorr@alumni.princeton.edu>

	* vtysh.1: Document new options -d and -E, and note that now multiple
	  -c options may be supplied, with embedded linefeed now supported.
	  In BUGS section, remove warning about vtysh causing a daemon
	  to freeze, since this has been fixed.
	* vtysh_main.c: (usage) Add new -d and -E options.  And note that
	  -c can be used multiple times, possibly with embedded linefeeds.
	  (longopts) Add new -d and -E options.
	  (main) Add new -d and -E options, and create a linked list to
	  support multiple -c options.  Do not call vtysh_connect_all until
	  after vtysh_read_config(config_default) and vtysh_auth have
	  succeeded.  This prevents the vtysh.conf file from configuring
	  any daemons, and it ensures that authentication has been passed
	  before we send any commands to any daemons.  Call vtysh_connect_all
	  with any daemon name supplied with -d.  If it is unable to connect
	  to any daemons, issue an error message and exit immediately.
	  When used in -c mode, call vtysh_execute("enable") before
	  executing the commands in order to match interactive behavior.
	  And detect embedded linefeed chars in -c commands and break them up
	  appropriately.
	* vtysh.h: (vtysh_connect_all) Fix proto to reflect new
	  daemon_name argument, and that it now returns an integer -- the
	  number of daemons to which we were able to connect.
	* vtysh.c: (vtysh_connect_all) Add a new daemon_name argument.
	  If supplied, connect only to that daemon.  And return
	  the number of daemons to which we were able to connect.
	  (vtysh_prompt): Performance enhancement -- make struct utsname
	  static so we call uname to get the hostname only once.