In Bash, how can option flag values be stored in variables? [duplicate]

Question

When writing Bash scripts, how can I obtain a value from the command-line when provided as part of option flags in the command line?

For example in the following:

./script --value=myText --otherValue=100

How could I store the myText and 100 values in the variables $text and $num?

Answer 1

Use getopts.

#!/bin/bash

while getopts ":a:" opt; do
  case $opt in
    a)
      echo "-a was triggered, Parameter: $OPTARG" >&2
      ;;
    \?)
      echo "Invalid option: -$OPTARG" >&2
      exit 1
      ;;
    :)
      echo "Option -$OPTARG requires an argument." >&2
      exit 1
      ;;
  esac
done