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Full Discussion: Take variable outside while loop
Top Forums Shell Programming and Scripting Take variable outside while loop Post 302907056 by Don Cragun on Wednesday 25th of June 2014 02:20:15 PM
Old 06-25-2014
You could also consider something like:
Code:
$!/bin/bash
var=$( [ -s /root/nums ] && tail -n 1 /root/nums || echo NONE )
printf '%s\n' "$var"

But, for small files, vbe's suggestion (with some added quotes) would faster:
Code:
#!/bin/bash
var="NONE"
while read -r entry
do
        var="$entry"
done</root/nums
printf '%s\n' "$var"

since this is only using shell built-ins.

I changed the echo to printf because the behavior of echo varies from shell to shell and system to system if the string to be printed starts with a minus sign (-) or contains a backslash character (\). And, if /root/nums is created by anything that is not under your direct control, you should be prepared to handle anything you might find there.
 

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LEARN ABOUT DEBIAN

pmvarrun

pmvarrun(8)							     pam_mount							       pmvarrun(8)

Name
       pmvarrun - updates /var/run/pam_mount/user

Syntax
       pmvarrun -u user [options]

Description
       A  separate  program is needed so that /var/run/pam_mount/user may be created with a pam_mount-specific security context (otherwise SELinux
       policy will conflict with gdm, which also creates file in /var/run).

       pmvarrun is flexible and can run in a number of different security setups:

   root-root
       When pmvarrun is invoked as root, /var/run/pam_mount's permission settings can be as strict as needed; usually (0755,root,root) is  a  good
       pick  as  it  gives  users the debug control over their refcount. Refcount files are given their respective owners (chowned to the user who
       logs in).

   user-user
       When invoked as the user who logs in, /var/run/pam_mount needs appropriate permissions to create a file, which means the write bit must	be
       set. It is also highly suggested to set the sticky bit in this case, so other users do not tamper with your refcount.

   root-user
       Some  programs or login helpers incorrectly call the PAM stack in a way that the login phase is done as root and the logout phase as a nor-
       mal user.  Nevertheless, pmvarrun supports this, and the same permissions as in root-root can be used. While the user may not  be  able	to
       unlink his file from /var/run/pam_mount, it will be truncated to indicate the same state.

Options
       --help, -h
	      Display help.

       --user user, -u user
	      User to handle, must be a valid username.

       --operation number, -o number
	      Increase volume count by number.

       -d     Turn on debugging.

Files
       /var/run/pam_mount/user

Author
       This  manpage  was originally written by Bastian Kleineidam <calvin@debian.org> for the Debian distribution of libpam-mount but may be used
       by others.

       See /usr/share/doc/packages/libpam-mount/copyright for the list of original authors of pam_mount.

pam_mount							    2008-10-08							       pmvarrun(8)
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