[PATCH v3 08/10] notmuch-{dump, restore}.1: document new format options

[David Bremner]

From: David Bremner <bremner at debian.org>

More or less arbitrarily, notmuch-dump.1 gets the more detailed
description of the format.
---
 man/man1/notmuch-dump.1    |   59 ++++++++++++++++++++++++++++++++++++++++++-
 man/man1/notmuch-restore.1 |   60 ++++++++++++++++++++++++++++++++++++++-----
 2 files changed, 111 insertions(+), 8 deletions(-)

diff --git a/man/man1/notmuch-dump.1 b/man/man1/notmuch-dump.1
index 9ccf35d..f4f7964 100644
--- a/man/man1/notmuch-dump.1
+++ b/man/man1/notmuch-dump.1
@@ -5,7 +5,8 @@ notmuch-dump \- Creates a plain-text dump of the tags of each message.
 .SH SYNOPSIS
 
 .B "notmuch dump"
-.RI "[ <" filename "> ] [--]"
+.RI "[ <" filename "> ]"
+.RB  [ "\-\-format=(sup|notmuch)"  "] [--]"
 .RI "[ <" search-term ">...]"
 
 .SH DESCRIPTION
@@ -20,6 +21,62 @@ recreated from the messages themselves.  The output of notmuch dump is
 therefore the only critical thing to backup (and much more friendly to
 incremental backup than the native database files.)
 
+.TP 4
+.B \-\-format=(sup|notmuch)
+
+Notmuch restore supports two plain text dump formats, both with one message-id
+per line, followed by a list of tags.
+
+.RS 4
+.TP 4
+.B sup
+
+The
+.B sup
+dump file format is specifically chosen to be
+compatible with the format of files produced by sup-dump.
+So if you've previously been using sup for mail, then the
+.B "notmuch restore"
+command provides you a way to import all of your tags (or labels as
+sup calls them).
+Each line has the following form
+
+.RS 4
+.RI < message-id >
+.B (
+.RI < tag "> ..."
+.B )
+
+with zero or more tags are separated by spaces. Note that (malformed)
+message-ids may contained arbitrary non-null characters. Note also
+that tags with spaces will not be correctly restored with this format.
+
+.RE
+
+.RE
+.RS 4
+.TP 4
+.B notmuch
+
+The
+.B notmuch
+dump format is intended to more robust against malformed message-ids
+and tags containing whitespace or non-\fBascii\fR(7) characters.
+Each line has the form
+
+.RS 4
+.RI < encoded-message-id "> <" encoded-tag "> ..."
+
+where encoded means that every byte not matching the regex
+.B [A-Za-z0-9+-_@=.:,]
+is replace by
+.B %nn
+where nn is the two digit hex encoding.
+
+
+.RE
+
+
 With no search terms, a dump of all messages in the database will be
 generated.  A "--" argument instructs notmuch that the
 remaining arguments are search terms.
diff --git a/man/man1/notmuch-restore.1 b/man/man1/notmuch-restore.1
index 2191df0..3fb0e99 100644
--- a/man/man1/notmuch-restore.1
+++ b/man/man1/notmuch-restore.1
@@ -5,7 +5,7 @@ notmuch-restore \- Restores the tags from the given file (see notmuch dump).
 .SH SYNOPSIS
 
 .B "notmuch restore"
-.RB [ "--accumulate" ]
+.RI  [  options "...]"
 .RI "[ <" filename "> ]"
 
 .SH DESCRIPTION
@@ -15,21 +15,67 @@ Restores the tags from the given file (see
 
 The input is read from the given filename, if any, or from stdin.
 
-Note: The dump file format is specifically chosen to be
+
+Supported options for
+.B restore
+include
+.RS 4
+.TP 4
+.B \-\-accumulate
+
+The union of the existing and new tags is applied, instead of
+replacing each message's tags as they are read in from the dump file.
+
+.RE
+.RS 4
+.TP 4
+.B \-\-format=(sup|notmuch|auto)
+
+Notmuch restore supports two plain text dump formats, with one message-id
+per line, followed by a list of tags.
+For details of the actual formats, see \fBnotmuch-dump\fR(1).
+
+.RS 4
+.TP 4
+.B sup
+
+The
+.B sup
+dump file format is specifically chosen to be
 compatible with the format of files produced by sup-dump.
 So if you've previously been using sup for mail, then the
 .B "notmuch restore"
 command provides you a way to import all of your tags (or labels as
 sup calls them).
 
-The --accumulate switch causes the union of the existing and new tags to be
-applied, instead of replacing each message's tags as they are read in from the
-dump file.
+.RE
+.RS 4
+.TP 4
+.B notmuch
 
-See \fBnotmuch-search-terms\fR(7)
-for details of the supported syntax for <search-terms>.
+The
+.B notmuch
+dump format is intended to more robust against malformed message-ids
+and tags containing whitespace or non-\fBascii\fR(7) characters.  This
+format hex-escapes all characters those outside of a small character
+set, intended to be suitable for e.g. pathnames in most UNIX-like
+systems.
 
 .RE
+
+.RS 4
+.TP 4
+.B auto
+
+This option (the default) tries to guess the format from the
+input. For correctly formed input in either supported format, this
+heuristic, based the fact that notmuch format contains no parentheses,
+should be accurate.
+
+.RE
+
+.RE
+
 .SH SEE ALSO
 
 \fBnotmuch\fR(1), \fBnotmuch-config\fR(1), \fBnotmuch-count\fR(1),
-- 
1.7.7.3