libmtp 1.1.19
The official libmtp documentation

Introduction

libmtp is a library for the Media Transfer Protocol (MTP) under various POSIX operating systems.

License

libmtp is available under the GNU Lesser General Public License, version 2. You can use libmtp in Free or proprietary software alike as long as you publish your modifications to this library in accordance with the LGPL license. If you do not follow the LGPL you will be in deep, deep trouble.