Add support for reading and writing SPV files.

[pspp] / doc / pspp-convert.texi

diff --git a/doc/pspp-convert.texi b/doc/pspp-convert.texi
index 3719de224c44dcb5fb1af537a417969e33c491a5..7af90a113ce9851f3208110e18cbb47820870eb0 100644 (file)
--- a/doc/pspp-convert.texi
+++ b/doc/pspp-convert.texi
@@ -1,3 +1,12 @@
+@c PSPP - a program for statistical analysis.
+@c Copyright (C) 2017 Free Software Foundation, Inc.
+@c Permission is granted to copy, distribute and/or modify this document
+@c under the terms of the GNU Free Documentation License, Version 1.3
+@c or any later version published by the Free Software Foundation;
+@c with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
+@c A copy of the license is included in the section entitled "GNU
+@c Free Documentation License".
+@c
 @node Invoking pspp-convert
 @chapter Invoking @command{pspp-convert}
 @cindex Invocation
@@ -50,8 +59,14 @@ formats.  Encrypted system file and syntax files are exceptions: if
 the input file is in an encrypted format, then the output file must be
 the same format (decrypted).  To decrypt such a file, specify the
 encrypted file as @var{input}.  The output will be the equivalent
-plaintext file.  You will be prompted for the password (or use
-@option{-p}, documented below).
+plaintext file.
+
+The password for encrypted files can be specified a few different
+ways.  If the password is known, use the @option{-p} option
+(documented below) or allow @command{pspp-convert} to prompt for it.
+If the password is unknown, use the @option{-a} and @option{-l}
+options to specify how to search for it, or @option{--password-list}
+to specify a file of passwords to try.
 
 Use @code{-O @var{extension}} to override the inferred format or to
 specify the format for unrecognized extensions.
@@ -87,6 +102,28 @@ necessary.
 Be aware that command-line options, including passwords, may be
 visible to other users on multiuser systems.
 
+When used with @option{-a} (or @option{--password-alphabet}) and
+@option{-l} (or @option{--password-length}), this option specifies the
+starting point for the search.  This can be used to restart a search
+that was interrupted.
+
+@item -a @var{alphabet}
+@item --password-alphabet=@var{alphabet}
+Specifies the alphabet of symbols over which to search for an
+encrypted file's password.  @var{alphabet} may include individual
+characters and ranges delimited by @samp{-}.  For example, @option{-a
+a-z} searches lowercase letters, @option{-a A-Z0-9} searches uppercase
+letters and digits, and @option{-a ' -~'} searches all printable ASCII
+characters.
+
+@item -l @var{max-length}
+@item --password-length=@var{max-length}
+Specifies the maximum length of the passwords to try.
+
+@item --password-list=@var{file}
+Specifies a file to read containing a list of passwords to try, one
+per line.  If @var{file} is @file{-}, reads from stdin.
+
 @item -h
 @itemx --help
 Prints a usage message on stdout and exits.