TODO file for gzip.Some of the planned features include:- Structure the sources so that the compression and decompression code  form a library usable by any program, and write both gzip and zip on  top of this library. This would ideally be a reentrant (thread safe)  library, but this would degrade performance. In the meantime, you can  look at the sample program zread.c.  The library should have one mode in which compressed data is sent  as soon as input is available, instead of waiting for complete  blocks. This can be useful for sending compressed data to/from interactive  programs.- Make it convenient to define alternative user interfaces (in  particular for windowing environments).- Support in-memory compression for arbitrarily large amounts of data  (zip currently supports in-memory compression only for a single buffer.)- Map files in memory when possible, this is generally much faster  than read/write. (zip currently maps entire files at once, this  should be done in chunks to reduce memory usage.)- Add a super-fast compression method, suitable for implementing  file systems with transparent compression. One problem is that the  best candidate (lzrw1) is patented twice (Waterworth 4,701,745  and Gibson & Graybill 5,049,881). The lzrw series of algorithms  are available by ftp in ftp.adelaide.edu.au:/pub/compression/lzrw*.- Add a super-tight (but slow) compression method, suitable for long  term archives.  One problem is that the best versions of arithmetic  coding are patented (4,286,256 4,295,125 4,463,342 4,467,317  4,633,490 4,652,856 4,891,643 4,905,297 4,935,882 4,973,961  5,023,611 5,025,258).  Note: I will introduce new compression methods only if they are  significantly better in either speed or compression ratio than the  existing method(s). So the total number of different methods should  reasonably not exceed 3. (The current 9 compression levels are just  tuning parameters for a single method, deflation.)- Add optional error correction. One problem is that the current version  of ecc cannot recover from inserted or missing bytes. It would be  nice to recover from the most common error (transfer of a binary  file in ascii mode).- Add a block size (-b) option to improve error recovery in case of  failure of a complete sector. Each block could be extracted  independently, but this reduces the compression ratio.- Use a larger window size to deal with some large redundant files that  'compress' currently handles better than gzip.- Implement the -e (encrypt) option.   Send comments to Jean-loup Gailly <jloup@chorus.fr>.