11-24-2006
i found it myself thank
if [ -z "$y" ]
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1. Shell Programming and Scripting
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2. Shell Programming and Scripting
I have the necessity to use this command:
cat file1 | grep $A | grep $B
where sometime A and, or, B are not set.
For example:
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never defined or set B
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Thanks.
Giovanni (1 Reply)
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Hello
I want to check for NULL variable..
but this is not working..please help
thanks in advance
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4. Shell Programming and Scripting
korn shell
If
then
update_smartcare_user_password "$u_id"
else
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fi
i get this error
Syntax error at line *** : `then' is not expected.
what should i do.
I want to check whether $a is null or not. (2 Replies)
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5. Shell Programming and Scripting
Hi all, I have a stupid question on NULL and zero(0).
In a script I've been working with, one of the lines is:
if &&
then
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Hello, Unix-forums!
My problem:
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Hi,
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Guys,
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sample.cfg
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10. Shell Programming and Scripting
DELETE=`cat $logfile1 | egrep -i "Delete" | sed 's/ */ /g' | cut -d" " -f2`
INSERT=`cat $logfile1 | egrep -i "Insert" | sed 's/ */ /g' | cut -d" " -f2`
UPDATE=`cat $logfile1 | egrep -i "Update" | sed 's/ */ /g' | cut -d" " -f2`
I need soming like below:
if value is null... (8 Replies)
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LEARN ABOUT DEBIAN
escape
escape(1) Mail Avenger 0.8.3 escape(1)
NAME
escape - escape shell special characters in a string
SYNOPSIS
escape string
DESCRIPTION
escape prepends a "" character to all shell special characters in string, making it safe to compose a shell command with the result.
EXAMPLES
The following is a contrived example showing how one can unintentionally end up executing the contents of a string:
$ var='; echo gotcha!'
$ eval echo hi $var
hi
gotcha!
$
Using escape, one can avoid executing the contents of $var:
$ eval echo hi `escape "$var"`
hi ; echo gotcha!
$
A less contrived example is passing arguments to Mail Avenger bodytest commands containing possibly unsafe environment variables. For
example, you might write a hypothetical reject_bcc script to reject mail not explicitly addressed to the recipient:
#!/bin/sh
formail -x to -x cc -x resent-to -x resent-cc
| fgrep "$1" > /dev/null
&& exit 0
echo "<$1>.. address does not accept blind carbon copies"
exit 100
To invoke this script, passing it the recipient address as an argument, you would need to put the following in your Mail Avenger rcpt
script:
bodytest reject_bcc `escape "$RECIPIENT"`
SEE ALSO
avenger(1),
The Mail Avenger home page: <http://www.mailavenger.org/>.
BUGS
escape is designed for the Bourne shell, which is what Mail Avenger scripts use. escape might or might not work with other shells.
AUTHOR
David Mazieres
Mail Avenger 0.8.3 2012-04-05 escape(1)