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content/blog/bashpartialargparse.md

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+---
+title: "Partial Argument Parse and Passing in Bash"
+date: 2020-09-07T21:33:26-04:00
+draft: false
+tags: []
+---
+
+Let's say we want to augment an existing terminal command (like for example `wget`). We then want to be able to add or edit command line options. The rest of this post provides an example that hopefully you can use in your bash script.
+
+```bash
+#!/bin/bash
+
+# Custom help function
+show_help() {
+  echo "Usage: custom_command [arguments]"
+  echo "    --name <name>"
+  echo "    --flag_example"
+  echo "    <additional arguments to be passed along>"
+  exit 0
+}
+
+# Defaults for our custom flags or parameters.
+name=""
+flag_example=0
+
+# Loop through and take out our custom parameters
+# from the parameter list.
+i=0
+numargs=$#
+while test $i -lt "$numargs"
+do
+  case "$1" in
+    "--help")
+      show_help
+      ;;
+    "--name")
+      shift
+      name=$1
+      ;;
+    "--flag_example")
+      flag_example=1
+      ;;
+    *)
+      set -- "$@" "$1"
+      ;;
+  esac
+  shift
+  i=$((i+1))
+done
+
+# Do something here using our custom parameters
+
+# Pass our non-custom parameters to the application
+wget "$@"
+```
+
+
+