Libwandio is a software library written in C that provides an API for transparent reading and writing of files using a variety of supported compression methods. Provided pthreads are available, I/O performance will be improved by doing any compression and/or decompression using a separate thread. Libwandio supports the popular compression methods (zlib, bzip2, LZMA, write-only LZO) and HTTP transport (read-only).