01-31-2012
What was the problem? And how was it solved? You should also read about the potential security vulnerabilities that come from using
eval (e.g.
Loading…, search for "eval"). As a matter of fact, you should try to stay away from eval, and only use it if absolutely necessary, and only on hard-coded values, never on strings that are input by user, or passed as arguments.
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
I'm not very familiar with the ssh command. When I tried to set a variable and then echo its value on a remote machine via ssh, I found a problem. For example,
$ ITSME=itsme
$ ssh xxx.xxxx.xxx.xxx "ITSME=itsyou; echo $ITSME"
itsme
$ ssh xxx.xxxx.xxx.xxx 'ITSME=itsyou; echo $ITSME'
itsyou
$... (3 Replies)
Discussion started by: password636
3 Replies
2. Shell Programming and Scripting
Hi there,
I've been scouring these forums and have found similar threads, but none apparently helped me solved my problem :rolleyes:
I'd like to run a command within a bash script, but that command is provided by the user to the script and may contain quotes, which is where the problem lies.... (9 Replies)
Discussion started by: cypression
9 Replies
3. UNIX for Dummies Questions & Answers
Hello,
I notice when I do echo $A and echo "$A" I get the same result but when I echo '$A' I get $A. What are the quotes used for then? (1 Reply)
Discussion started by: mojoman
1 Replies
4. Shell Programming and Scripting
Hi guys, I have a sed line in double quotes which works fine, but I want it to be in single quotes
here is the sed line
sed "/abc_def/s/\'.*\'/\'\${abc_def}\'/"
can some one give the equivalent to the above script in single quotes
Thanks a ton (5 Replies)
Discussion started by: sol_nov
5 Replies
5. UNIX for Dummies Questions & Answers
Unix superusers,
I am new to unix but would like to learn more about grep. I am very familiar with regular expressions as i have used them for searching text files in windows based text editors. Since I am not very familiar with Unix, I dont understand when one should use GREP with the... (2 Replies)
Discussion started by: george_vandelet
2 Replies
6. Shell Programming and Scripting
Hello,
is it possible to give grep two documents to surche for? like
grep "test" /home/one.txt AND /home/two.txt ?
thanks (1 Reply)
Discussion started by: Cybertron
1 Replies
7. Shell Programming and Scripting
Hello. I'm trying to write a bash script that uses GNU screen and have hit a brick wall that has cost me many hours... (I'm sure it has something to do with quoting/globbing, which is why I post it here)
I can make a script that does the following just fine:
test.sh:
#!/bin/bash
# make... (2 Replies)
Discussion started by: jondecker76
2 Replies
8. Shell Programming and Scripting
Hi,
Trying to change the prompt. I have the following code.
export PS1='
<${USER}@`hostname -s`>$ '
The hostname is not displayed
<abc@`hostname -s`>$ uname -a
AIX xyz 1 6 00F736154C00
<adcwl4h@`hostname -s`>$
If I use double quotes, then the hostname is printed properly but... (3 Replies)
Discussion started by: bobbygsk
3 Replies
9. Shell Programming and Scripting
Hello everyone,
I am working on a file with thousands of lines and instead of manually removing them I need a script to remove quotes within quotes. For example a line may have something such as this:
"Hey, I was ready to go on stage or "break a leg", but I failed miserably."
So I need to... (15 Replies)
Discussion started by: tastybrownies
15 Replies
10. Shell Programming and Scripting
Hi All,
I'm unable to load the data using sql loader where there are double quotes within the double quotes As these are optionally enclosed by double quotes.
Sample Data :
"221100",138.00,"D","0019/1477","44012075","49938","49938/15043000","Television - 22" Refurbished - Airwave","Supply... (6 Replies)
Discussion started by: mlavanya
6 Replies
LEARN ABOUT OPENSOLARIS
eval
eval(1T) Tcl Built-In Commands eval(1T)
__________________________________________________________________________________________________________________________________________________
NAME
eval - Evaluate a Tcl script
SYNOPSIS
eval arg ?arg ...?
_________________________________________________________________
DESCRIPTION
Eval takes one or more arguments, which together comprise a Tcl script containing one or more commands. Eval concatenates all its argu-
ments in the same fashion as the concat command, passes the concatenated string to the Tcl interpreter recursively, and returns the result
of that evaluation (or any error generated by it). Note that the list command quotes sequences of words in such a way that they are not
further expanded by the eval command.
EXAMPLE
This procedure acts in a way that is analogous to the lappend command, except it inserts the argument values at the start of the list in
the variable:
proc lprepend {varName args} {
upvar 1 $varName var
# Ensure that the variable exists and contains a list
lappend var
# Now we insert all the arguments in one go
set var [eval [list linsert $var 0] $args]
}
KEYWORDS
concatenate, evaluate, script
SEE ALSO
catch(1T), concat(1T), error(1T), list(1T), subst(1T), tclvars(1T)
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Availability | SUNWTcl |
+--------------------+-----------------+
|Interface Stability | Uncommitted |
+--------------------+-----------------+
NOTES
Source for Tcl is available on http://opensolaris.org.
Tcl eval(1T)