Shell Programming and Scripting

Behavior I am looking for:

Code:

$ for var in a 'b c'; do echo $var; done
a
b c

What I am getting when I try to use a variable:

Code:

$ test="a 'b c'"
$ for var in $test; do echo $var; done
a
'b
c'

Is there a workaround?

Mike

How about this:

Code:

$ test=(a 'b c')
$ for var in "${test[@]}"; do echo $var; done
a
b c

or

Code:

$ set a 'b c'
$ while [ $# -gt 0 ]; do echo $1; shift ; done
a
b c

This does not get around my problem of having variable input.

Code:

 
test=($some_some_variable_with_quotes)

breaks it.

Mike

---------- Post updated at 02:14 PM ---------- Previous update was at 02:02 PM ----------

I'm currently working on a workaround that uses \n

Whatever code is parsing arguments in bash works the way I want this to work

Code:

 
script Argument1 "Argument 2" 'Argument 3'

sets $1 $2 and $3 just as you would expect/want

I am trying to parse commands from STDIN or a file the same way.

Mike

I guess here you are trying to avoid using eval:

Code:

eval test=($some_some_variable_with_quotes)

Shell doesn't do that kind of doublethink. If something's in a variable, it's taken literally (with the exception of glob characters).

Just like in your other thread:

If you explain your actual goal -- not the means you've picked to accomplish it -- we could help you far better!

Your questions suggest you've taken a wrong turn and ended up building a shell-inside-the-shell kind of thing, instead of just using the shell's features in the first place (i.e. building a configuration-file-reader in the shell, instead of just sourcing the file). Not knowing what the shell can do often leads to this kind of catch-22 situation.

But for the record, the xargs utility can understand quotes and print properly grouped lines:

Code:

$ xargs -n 1 <<EOF
a b c d e
"1 2 3 4 5"
'q asdf ads f'
EOF

a
b
c
d
e
1 2 3 4 5
q asdf ads f

$

I thought I did just that above. I'll try again:

I have a file with argments in it. There can be multiple arguments per line. Arguments can contain whitespace (in which case they are quoted). I want to itterate through them and handle them (such as with a case statement). I want the itteration to separate on unqoted white space but not quoted whitespace.

Mike

PS. Will check out the evel suggestion.
PPS. Will check out the xargs suggestion too.

Never use eval if you can possibly avoid it. If your file contains `rm -Rf ~/` and you feed that text into eval, eval will execute that code!

You explained one tiny corner of one tiny corner of your problem. What exactly is this line-by-line loader thing for? Is it a part of anything larger?