Question

I am writing a shell script which needs to pull values out of a text file which looks like this:

app.full.name /warfilelocation/ warfilename

My shell script will be iterating over a list of application names and pulling out either the location or name using AWK. I have tested doing this on the command line using the following:
awk “\$1 ~/app.full.name/ { print $2 }” applications.txt

which returns what I would expect however when i put this in a shell script I start having issues.

I have a function that looks like this:

function get_location() {
        local application=$1
        awk "\$1 ~/^$application/ { print \$2 }"  applications.txt 
}

But when i call this function i get the following error:

awk: $1 ~/^app.full.name
awk:      ^ unterminated regexp
awk: cmd. line:1: app.full.name
awk: cmd. line:1:         ^ syntax error
awk: cmd. line:2: app.full.name/ { print $2 }
awk: cmd. line:2:    ^ syntax error

Does anyone have any ideas what I am doing wrong here. I presume I am not escaping the variable correct but no matter what i try it doesnt seem to work.

Thanks in advance

Answer 1

Use this approach to make awk recognize shell variables:

awk -v "v1=$VAR1" -v "v2=$VAR2" '{print v1, v2}' input_file

Update

$ cat input
tinky-winky
dipsy
laa-laa
noo-noo
po

$ teletubby='po'

$ awk -v "regexp=$teletubby" '$0 ~ regexp' input
po

Note that anything could go into the shell-variable,
even a full-blown regexp, e.g ^d.*y. Just make sure to use single-quotes
to prevent the shell from doing any expansion.