Using bash, I'm trying to read a .properties file (name=value pairs), assigning an indirect variable reference for each line in the file.
The trick is that a property's value string may contain the name of a property that occurred earlier in the file, and I want the name of the 1st property to... (5 Replies)
The construct ${#parameter} returns the number of characters in the parameter and ${!parameter} specifies an indirect variable. My question is: How do I combine these two. What I want is ${#!parameter} but this gives an error.
Of course I can use:
dummy=${!parameter}
${#dummy}
but that's a... (0 Replies)
Ummm can anybody help me with this one?
Its prob quite simple.
I bascially have a file name say J1x2x3x7.dat
Im using the file name as a variable in a bash script. Want I want to do is extract most of the file name and make it a new variable expect with say one of the number now a... (2 Replies)
Hi,
I've got a small problem.
If varible A stores "B" and Variable B stores C,
How to get the value of variable B by using only Variable A..?
I tried the following but didnt work pease help..
$ var1=vikram
$ echo $var1
vikram
$ vikram=sampath
$ echo $vikram
sampath
$ echo... (6 Replies)
Hi
I have variable A_B=alpha
also var1="A"
var2="B"
I want to retrieve the value alpha using var1 and var2 , somthing like
echo ${${var1}_${var2}} that works. Obviously this is receiving syntax
error (6 Replies)
Hello,
is there a kind soul who can answer me, does the SH support double substitution known as indirect expansion similar to BASH? The syntax for bash is ${!var}.
For instance in bash I can write something like this:
VAR="value"
REF_VAR="VAR"
echo ${!REF_VAR}
and get the "value"... (1 Reply)
I have a file with two columns of numbers (member IDs):
1 1
2 1
3 1
4 2
5 4
6 1
7 5
8 3
9 2
Think of column 1 as the referee and column 2 as the referrer.
Is there a good way to backtrack who referred who? I would like an output, for this example here to be:
1 1
2 1
3 1
4 2 1 (2 Replies)
Sometimes it is handy to protect long scripts in C++.
The following syntax works fine for simple commands:
#define SHELLSCRIPT1 "\
#/bin/bash \n\
echo \"hello\" \n\
"
int main ()
{
cout <<system(SHELLSCRIPT1);
return 0;
}
Unfortunately for there are problems for:
1d arrays:... (10 Replies)
Trying to do so
echo "111:222:333" |awk -F: '{system("export TESTO=" $2)}'But it doesn't work (2 Replies)
Discussion started by: urello
2 Replies
LEARN ABOUT MOJAVE
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)