Check for flag passed to a Bash script and process value

Question

I have a bash script in which I want to check if a flag with value was passed to it and then use the value in a variable. Something like this (pseudocode):

file.sh -c 1.0.0

inside file.sh :

#!/bin/bash

get flag:
if flag 'c' then 
curl c
else 
curl 'something else'

Whats the most optimal way to do the above?

@TharangaAbeyseela what if no argument if passed ? the script would just fail. — Scooby, Feb 17 '17 at 22:01
please check the answer. sorry i hit the enter before completion :) — Tharanga Abeyseela, Feb 17 '17 at 22:09
[BashFAQ #35](http://mywiki.wooledge.org/BashFAQ/035) covers the topic in detail. Note that `getopt` is **not** a preferred solution. — Charles Duffy, Feb 17 '17 at 22:10

score 3 · Accepted Answer · answered Feb 17 '17 at 22:08

3

try the following

#!/bin/bash


while getopts ":c" opt; do
 case $opt in
 c)
    echo "-c was triggered!" >&2
    ;;
 \?)
    echo "Invalid option: -$OPTARG" >&2
    ;;
 esac
done

answered Feb 17 '17 at 22:08

Tharanga Abeyseela

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Check for flag passed to a Bash script and process value

1 Answers1