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-rw-r--r--README24
1 files changed, 13 insertions, 11 deletions
diff --git a/README b/README
index b4059bf..046cf54 100644
--- a/README
+++ b/README
@@ -1,13 +1,15 @@
Description
Tarlz is a massively parallel (multi-threaded) combined implementation of
-the tar archiver and the lzip compressor. Tarlz creates, lists, and extracts
-archives in a simplified and safer variant of the POSIX pax format
-compressed with lzip, keeping the alignment between tar members and lzip
-members. The resulting multimember tar.lz archive is fully backward
-compatible with standard tar tools like GNU tar, which treat it like any
-other tar.lz archive. Tarlz can append files to the end of such compressed
-archives.
+the tar archiver and the lzip compressor. Tarlz uses the compression library
+lzlib.
+
+Tarlz creates tar archives using a simplified and safer variant of the POSIX
+pax format compressed in lzip format, keeping the alignment between tar
+members and lzip members. The resulting multimember tar.lz archive is fully
+backward compatible with standard tar tools like GNU tar, which treat it
+like any other tar.lz archive. Tarlz can append files to the end of such
+compressed archives.
Keeping the alignment between tar members and lzip members has two
advantages. It adds an indexed lzip layer on top of the tar archive, making
@@ -16,7 +18,7 @@ amount of data lost in case of corruption. Compressing a tar archive with
plzip may even double the amount of files lost for each lzip member damaged
because it does not keep the members aligned.
-Tarlz can create tar archives with five levels of compression granularity;
+Tarlz can create tar archives with five levels of compression granularity:
per file (--no-solid), per block (--bsolid, default), per directory
(--dsolid), appendable solid (--asolid), and solid (--solid). It can also
create uncompressed tar archives.
@@ -40,8 +42,8 @@ archive, but it has the following advantages:
lziprecover can be used to recover some of the damaged members.
* A multimember tar.lz archive is usually smaller than the corresponding
- solidly compressed tar.gz archive, except when compressing files
- smaller than about 32 KiB individually.
+ solidly compressed tar.gz archive, except when individually
+ compressing files smaller than about 32 KiB.
Note that the POSIX pax format has a serious flaw. The metadata stored in
pax extended records are not protected by any kind of check sequence.
@@ -85,7 +87,7 @@ tar.lz
+===============+=================================================+========+
-Copyright (C) 2013-2020 Antonio Diaz Diaz.
+Copyright (C) 2013-2021 Antonio Diaz Diaz.
This file is free documentation: you have unlimited permission to copy,
distribute, and modify it.