Taking filename as input when running script

Question

I have created a shell script which reads from csv File A (INPUT.csv) and then creates interim file from the data, do some operations and create another csv File B. Later at the end it merges the two files INPUT.csv and B together to generate FinalOutput.csv.

Limitation of the script is if the file name is different then I have to either rename the file or make the change in the script else it will not read. How can I make this dynamic so that whatever the name of the file is -- it should process and create the FinalOutput.csv

Sample script -

#!/bin/bash
awk -F, '{print $2}' INPUT.csv > FileB.csv
{
Operations on File B
}
paste -d "," INPUT.csv FileB.csv > FinalOutput.csv

exit 0

It would help to see the actual script. Edit your question and include it. Hint: pass the file names as parameters. — Panki, Aug 07 '20 at 12:46
Does this answer your question? [Pass command line arguments to bash script](https://unix.stackexchange.com/questions/32290/pass-command-line-arguments-to-bash-script) — AdminBee, Aug 11 '20 at 07:12

score 3 · Accepted Answer · edited Aug 07 '20 at 13:10

3

Take the filenames of the input files as parameters when running the script.

You would then run the script with:

./script.sh INPUT.csv FileB.csv

Inside the script, refer to the parameters with variables "$1" and "$2", like this:

#!/bin/bash
awk -F, '{print $2}' "$1" > "$2"
{
# Operations on File B
}
paste -d "," "$1" "$2" > FinalOutput.csv

exit 0

edited Aug 07 '20 at 13:10

Panki

6,221
2
24
33

answered Aug 07 '20 at 13:06

Artur Meinild

682
5
15

1

You were a bit faster than me. You're missing quotes around parameters. Also, I believe OP wants *both* FileB and INPUT to be assignable. – Panki Aug 07 '20 at 13:08
Are quotes around the parameters required? I would believe it works just fine without. At least I have a lot of scripts with unquoted parameters that work without problem. – Artur Meinild Aug 07 '20 at 13:10
See https://www.tldp.org/LDP/abs/html/quotingvar.html – Panki Aug 07 '20 at 13:11
Right - maybe in this particular case it would not make a difference, but generally a better idea - agreed! – Artur Meinild Aug 07 '20 at 13:15
Thanks.. This solved the problem. – RAHUL SONI Aug 07 '20 at 13:23
It's often helpful to assign the positional parameters to variables with more descriptive names. – glenn jackman Aug 07 '20 at 16:41

Taking filename as input when running script

1 Answers1