Check if a variable is having value Post: 302769401

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Top Forums Shell Programming and Scripting Check if a variable is having value Post 302769401 by kg_gaurav on Tuesday 12th of February 2013 06:18:41 AM

02-12-2013

Registered User

Quote:

Originally Posted by anil510

I have a script /root/asas with following contents.

Code:

#!/bin/bash

ha=`cat /etc/passwd | grep sandra`

if [ -n $ha ]; then
        echo "Sandra is in /etc/passwd"
        echo "variable ha is $ha"
else
        echo "Sandra is NOT in /etc/passwd"
        echo "variable ha is $ha"

fi

What I need is when "cat" does not find sandra in /etc/passwd, it should print "Sandra is NOT in /etc/passwd". But this is not giving correct result. See below.

Code:

[root@server ]# grep sandra /etc/passwd
#sandra

[root@server ]# sh /root/asas
Sandra is in /etc/passwd
variable ha is #sandra

[root@server ]# grep sandra /etc/passwd  --> sandra removed from /etc/passwd

[root@server ]# sh /root/asas
Sandra is in /etc/passwd  --> supposed to be "Sandra is NOT in /etc/passwd"
variable ha is

If you just want to print Sandra is NOT in /etc/passwd" then why are you using " echo "variable ha is $ha" in else of your script?

kg_gaurav

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LEARN ABOUT OPENSOLARIS

vino-passwd

vino-passwd(1)							   User Commands						    vino-passwd(1)

NAME

       vino-passwd - change vino login password

SYNOPSIS

       vino-passwd [--help] [--version]

DESCRIPTION

       vino-passwd is a command line tool to change the vino login password.

OPTIONS

       These  programs	follow	the  usual GNU command line syntax, with long options starting with two dashes (`-'). A summary of options for the
       command vino-passwd is included below.

       -?, --help	       display this help and exit

       -v, --version	       output version information and exit

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWgnome-remote-desktop	   |
       +-----------------------------+-----------------------------+
       |Interface stability	     |Volatile			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       vino-server(1), vino-preferences(1), attributes(5), gnome-std-options(5)

NOTES

       Written by Halton Huo, Sun Microsystems Inc., 2008.

SunOS 5.11							    15 Aug 2008 						    vino-passwd(1)

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