Linked Questions
12 questions linked to/from Are quotes needed for local variable assignment?
4
votes
1
answer
500
views
What are the contexts where Bash doesn't perform word splitting and globbing?
Bash doesn't perform word splitting in globbing in these cases:
LHS or RHS of an assignment, except for indexed arrays
var=$value # simple variable
declare -A hash
key=&...
275
votes
4
answers
52k
views
Security implications of forgetting to quote a variable in bash/POSIX shells
If you've been following unix.stackexchange.com for a while, you
should hopefully know by now that leaving a variable
unquoted in list context (as in echo $var) in Bourne/POSIX
shells (zsh being the ...
46
votes
3
answers
35k
views
Using shell variables for command options
In a Bash script, I'm trying to store the options I'm using for rsync in a separate variable. This works fine for simple options (like --recursive), but I'm running into problems with --exclude='.*':
...
216
votes
3
answers
103k
views
$VAR vs ${VAR} and to quote or not to quote
I can write
VAR=$VAR1
VAR=${VAR1}
VAR="$VAR1"
VAR="${VAR1}"
the end result to me all seems about the same. Why should I write one or the other? are any of these not portable/POSIX?
34
votes
2
answers
4k
views
Where is "export var=value" not available?
I have picked up -- probably on Usenet in the mid-1990s (!) -- that the construct
export var=value
is a Bashism, and that the portable expression is
var=value
export var
I have been advocating ...
204
votes
3
answers
186k
views
Quoting within $(command substitution) in Bash
In my Bash environment I use variables containing spaces, and I use these variables within command substitution.
What is the correct way to quote my variables? And how should I do it if these are ...
1
vote
0
answers
51
views
Is there any point in quoting simple strings? [duplicate]
Is there any reason for doing something like:
a="abc"
or
a='abc'
The quotes seem completely superfluous, but then there might be some hideous corner case... I'm interested in Bash and Sh in ...
-1
votes
3
answers
27k
views
How to add more directiories in PATH [closed]
Okay, first thing first, I'm new to Linux and I'm using Linux Mint.
I learned that when I want to add more directories to my PATH (specifically my home directory) I need a Bash command that looks ...
9
votes
4
answers
5k
views
back ticks vs double quotes
I've been wondering this for a long time but haven't figured out how to look it up -
is this:
x=`command -v r2g`
the same as this:
x="$(command -v r2g)"
or is it the same as this:
x=$(command -...
2
votes
2
answers
389
views
Why is it not required to double quote `$bar` in assignment `foo=$bar`? [duplicate]
From https://unix.stackexchange.com/a/32227/674
The main places where it's safe not to use the double quotes are:
in an assignment: foo=$bar (but note that you do need the double quotes in ...
1
vote
2
answers
3k
views
Saving Output In a Variable and Re-using it
page=`grep $x /var/www/vhosts/example.com/statistics/logs/access_log | awk '{print $7}'| sort |uniq -c |sort -nr`
times=`$page | wc -l`
I am trying to save output of grep in a variable as page.
But ...
1
vote
2
answers
6k
views
ls, mv, cp, cat, vi, command not found
I was trying to add a new path to my bashrc file but I have seemed to messed something up. after I $ source ~/.bashrc I no longer can use the commands ls, mv, cp, cat, vi, and probably others that I ...