A script that can watch a .c file for changes and if it detects a change it will recompile and run it again. Modified from a Stackoverflow answer.

watch-c-file.sh

#!/bin/bash
read -p 'Which c file to watch?: ' file_name
read -p 'Which gcc flags? Type them all with a space between: ' opt_flags
old_file_sig=$(stat -c %Z $file_name)
echo "Watching $file_name for changes..."
while true
do
  new_file_sig=$(stat -c %Z $file_name)
  if [[ "$new_file_sig" != "$old_file_sig" ]]; then
        echo ""
        echo "$file_name changed... compiling and running"
        echo ""
        gcc $file_name -O $opt_flags -o $file_name.o && ./$file_name.o
        old_file_sig=$new_file_sig
        echo ""
        echo "Watching $file_name for changes..."
  fi
  sleep 1
done