From 0dbd88db3933fac9c79adb107ab4a6932f33ea99 Mon Sep 17 00:00:00 2001 From: Ludovic Courtès Date: Fri, 21 Feb 2014 20:22:57 +0100 Subject: doc: More on what's special about the archive format. * doc/guix.texi (Invoking guix archive): Expound on what sets the Nar format apart. --- doc/guix.texi | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) (limited to 'doc') diff --git a/doc/guix.texi b/doc/guix.texi index b2733fbec9..36e68668ef 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -1095,11 +1095,19 @@ the target machine's store. The @code{--missing} option can help figure out which items are missing from the target's store. Archives are stored in the ``Nix archive'' or ``Nar'' format, which is -comparable in spirit to `tar'. When exporting, the daemon digitally -signs the contents of the archive, and that digital signature is -appended. When importing, the daemon verifies the signature and rejects -the import in case of an invalid signature or if the signing key is not -authorized. +comparable in spirit to `tar', but with a few noteworthy differences +that make it more appropriate for our purposes. First, rather than +recording all Unix meta-data for each file, the Nar format only mentions +the file type (regular, directory, or symbolic link); Unix permissions +and owner/group are dismissed. Second, the order in which directory +entries are stored always follows the order of file names according to +the C locale collation order. This makes archive production fully +deterministic. + +When exporting, the daemon digitally signs the contents of the archive, +and that digital signature is appended. When importing, the daemon +verifies the signature and rejects the import in case of an invalid +signature or if the signing key is not authorized. @c FIXME: Add xref to daemon doc about signatures. The main options are: -- cgit 1.4.1