Friends,
I did following exercise
$ echo '' > test
$ od -b test
$ echo "">test
$ od -b test
$echo > test
$od -b test
Every time I got the following output
0000000 012
0000001
But 012 is octal value for new line character .
Even though there is no apperent new line character... (6 Replies)
:D my first question is how can envoke filename expansion from within a shell script.. forinstance if i execute the script and it asks for a specific directory that i would like to cd to, how can i get the script to use the same file name expension as the command line..
my second question is how... (3 Replies)
Can anyone tell me if there is a way to remove the encryption from Data CDs by UNIX? Or does anyone know of a program that can remove the encryption?
I would much appreciate it!
Thanks,
-Peaves (2 Replies)
Hello. I'm a complete newbie to C programming. I have a C program that wasn't written by me where I need to write some wrappers around it to automate and make it easier for a client to use. The problem is that the program accepts standard input to control the program... I'm hoping to find a simple... (6 Replies)
If given some output such as:
"I'm having a senior moment"
How do you print the last six characters to the screen?
I'm thinking with awk or sed but can't remember how. (1 Reply)
Hey guys! This is my first post, as im new here :S
I have a simple problem for a big program.
We have a .sh to install it, but when I run the .sh in terminal like i should, It says the class is not found. I believe it has to do with the syntax, as the person who made it is not a linux pro. I... (3 Replies)
Hi Guys,
I've been learning UNIX for the past couple of days and I came across this exercise, I can't get my head around it, so I would be ever so grateful if I could receive some sort of help or direction with this.
Create a file with x amount of lines in it, the content of your choice. ... (3 Replies)
Cheers!
In /etc/syslog.conf, if an error type is not specified, is it logged anywhere (most preferable is it logged to /var/log/messages) or not?
To be more precise I am interested in error and critical level messages. At default these errors are not specified in syslog.conf, and I need to... (6 Replies)
Discussion started by: dr1zzt3r
6 Replies
LEARN ABOUT ULTRIX
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)