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Full Discussion: Precedence in operators issue
Top Forums Shell Programming and Scripting Precedence in operators issue Post 302504467 by Perderabo on Monday 14th of March 2011 04:52:39 PM
Old 03-14-2011
It works for me...if the user is in /etc/passwd...
Code:
$
$ ABC=mail
$ grep mail /etc/passwd
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
mailnull:x:47:47::/var/spool/mqueue:/sbin/nologin
$ cd ~${ABC}
$ pwd
/var/spool/mail
$
$ ABC=fubar
$ cd ~${ABC}
ksh: cd: ~fubar: [No such file or directory]
$

 

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LEARN ABOUT DEBIAN

viewsu

VIEW-OS(1)						      General Commands Manual							VIEW-OS(1)

NAME

       viewsu - change (virtual) user ID or become (virtual) superuser

SYNOPSIS

       viewsu [options] [username]

DESCRIPTION

       The viewsu command is used to become another user during a login session. Invoked without a username, viewsu defaults to becoming the supe-
       ruser. The optional argument - may be used to provide an environment similar to what the user would expect had the user logged in directly.
       This  command  is  the  View-OS	counterpart  of  the  su(1)  command.	The  value of $PATH is reset to /bin:/usr/bin for normal users, or
       /sbin:/bin:/usr/sbin:/usr/bin for the superuser. This may be changed with the ENV_PATH and ENV_SUPATH definitions in /etc/login.defs.

OPTIONS

       The options which apply to the viewsu command are:

       -c, --command COMMAND
	   Specify a command that will be invoked by the shell using its -c.

       -, -l, --login
	   Provide an environment similar to what the user would expect had the user logged in directly.

	   When - is used, it must be specified as the last viewsu option. The other forms (-l and --login) do not have this restriction.

       -s, --shell SHELL
	   The shell that will be invoked.

	   The invoked shell is chosen from (highest priority first):

	   o   The shell specified with --shell.

	   o   The shell indicated in the /etc/passwd entry for the target user.

	   o	/bin/sh if a shell could not be found by any above method.

SEE ALSO

       su(1), linux.defs(5)

AUTHORS

       View-OS is a project of the Computer Science Department, University of Bologna. Project Leader: Renzo Davoli.
       <http://www.sourceforge.net/projects/view-os>

       Howto's and further information can be found on the project wiki <wiki.virtualsquare.org>.

NOTE

       Most part of the text is taken from su(1).

VIEW-OS: a process with a view					  August 5, 2009							VIEW-OS(1)
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