Replace the current process with another process.
# To replace with the specified command using the current environment variables:
exec <command -with -flags>
# To replace with the specified command using initialized environment variables:
exec -c <command -with -flags>
# To replace with the specified command and login to the default shell:
exec -l <command -with -flags>
# To replace with the specified command and rename the process name:
exec -a <process_name> <command -with -flags>