mktemp creates temporary files in a secure manner. It is used in scripts. tempfile creates temporary files in a less secure manner than mktemp. It is installed for backwards-compatibility. The http-get script takes advantage of a little known feature of bash called "net redirection". It is used to download from websites without using any other programs. iana-net uses the http-get script to simplify the process of procuring IANA's services and protocols configuration files.