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@@ -11,8 +11,36 @@ multiprocessor machines, which makes it specially well suited for
distribution of big software files and large scale data archiving. On
files big enough, plzip can use hundreds of processors.
+Plzip replaces every file given in the command line with a compressed
+version of itself, with the name "original_name.lz". Each compressed
+file has the same modification date, permissions, and, when possible,
+ownership as the corresponding original, so that these properties can be
+correctly restored at decompression time. Plzip is able to read from some
+types of non regular files if the "--stdout" option is specified.
-Copyright (C) 2009, 2010, 2011, 2012 Antonio Diaz Diaz.
+If no file names are specified, plzip compresses (or decompresses) from
+standard input to standard output. In this case, plzip will decline to
+write compressed output to a terminal, as this would be entirely
+incomprehensible and therefore pointless.
+
+Plzip will correctly decompress a file which is the concatenation of two
+or more compressed files. The result is the concatenation of the
+corresponding uncompressed files. Integrity testing of concatenated
+compressed files is also supported.
+
+As a self-check for your protection, plzip stores in the member trailer
+the 32-bit CRC of the original data and the size of the original data,
+to make sure that the decompressed version of the data is identical to
+the original. This guards against corruption of the compressed data, and
+against undetected bugs in plzip (hopefully very unlikely). The chances
+of data corruption going undetected are microscopic, less than one
+chance in 4000 million for each member processed. Be aware, though, that
+the check occurs upon decompression, so it can only tell you that
+something is wrong. It can't help you recover the original uncompressed
+data.
+
+
+Copyright (C) 2009, 2010, 2011, 2012, 2013 Antonio Diaz Diaz.
This file is free documentation: you have unlimited permission to copy,
distribute and modify it.