* guix/download.scm (download-to-store): When URI is #f, assume that URL
  is a file name, and handle it.

* gnu/packages/gcc.scm (gcc-4.7): Change /nix/store in comment.
* gnu/system/vm.scm (operating-system-default-contents):
  Use (%store-prefix) instead of "/nix/store".
* guix/derivations.scm (derivation-path->output-path,
  derivation-path->output-paths): Change to /gnu/store in docstring.

* guix/build/linux-initrd.scm (make-essential-device-nodes): Create
  /dev/ptmx and /dev/pts.
* gnu/system/vm.scm (qemu-image): Umount /fs/dev/pts before /fs.

* tests/store.scm ("topologically-sorted, more difficult"): Arrange to
  handle a different ordering of (references %store y).

* gnu/packages/linux.scm (unionfs-fuse): New variable.

* HACKING (Submitting Patches): Mention 'git send-mail'.
* doc/guix.texi (Packaging Guidelines): More details on how to prepare a
  package module.
  (Contributing): Add reference to #guix channel on Freenode.

Co-authored-by: Ludovic Courtès <ludo@gnu.org>

* gnu/packages/pretty-print.scm (source-highlight): Change "boost-1.54" input
  to "boost"

* guix/scripts/offload.scm (offload): Remove default value for
  'build-timeout'.  Pass '--timeout' to the remote 'guix build'
  process.
  (transfer-and-offload, process-request): Remove default value for
  'build-timeout'.

* guix/scripts/build.scm (show-build-options-help): Document
  '--timeout'.
  (set-build-options-from-command-line): Pass #:timeout to
  'set-build-options'.
  (%standard-build-options): Add '--timeout'.
* doc/guix.texi (Invoking guix build): Document it.

* guix/serialization.scm (write-string-pairs): New procedure.
* guix/store.scm (write-arg): Add 'string-pairs' case.
  (set-build-options): Add 'timeout' keyword parameter.  Honor it.
* tests/derivations.scm ("build-expression->derivation and timeout"):
  New test.

* gnu/packages/admin.scm (libpcap, jnettop): New variables.

* daemon.am (libstore_a_CPPFLAGS): Change /nix to /guix.
* guix/config.scm.in (%state-directory): Likewise.
* guix/store.scm (log-file): Likewise.

* configure.ac: Change the default 'storedir' to /gnu/store.  Print
  $storedir.
* doc/guix.texi: Replace "/nix/store" by "/gnu/store", except where
  describing Nix compatibility.
* Makefile.am: Likewise.

* guix/scripts/offload.scm (lock-file, unlock-file, with-file-lock,
  with-machine-lock, machine-slot-file, acquire-build-slot,
  release-build-slot): Move definitions above their first use.

* gnu/packages/rdf.scm (soprano): Add input raptor2.

* guix/scripts/offload.scm (transfer-and-offload): New procedure, with
  core formerly in 'process-request'.
  (choose-build-machine): Remove 'requirements' parameter.
  (process-request): Reply 'decline' when none of MACHINES matches the
  requirements, and 'postpone' when MACHINES are busy.

* gnu/packages/rdf.scm (raptor2): Disable parallel tests since it makes
    tests fail.

* guix/scripts/offload.scm (%slots): New variable.
  (choose-build-machine): Add SLOT to '%slots'.

* guix/scripts/offload.scm (choose-build-machine)[machine+slots]: Use
  'filter-map', not 'filter'.

* guix/scripts/offload.scm (machine-choice-lock-file,
  machine-slot-file, acquire-build-slot, release-build-slot): New
  procedures.
  (choose-build-machine): Operate with (machine-choice-lock-file)
  taken.  Acquire a build slot for each of MACHINES.  Release those not
  used.

* guix/scripts/offload.scm (lock-machine, unlock-machine): Remove.
  (lock-file, unlock-file): New procedures.
  (with-file-lock): New macro.
  (with-machine-lock): Rewrite in terms of 'with-file-lock'.

* guix/scripts/offload.scm (lock-machine): Add 'hint' parameter.
  (unlock-machine): Remove 'machine' parameter.
  (with-machine-lock): Add 'hint' parameter, and pass it down.
  (process-request): Adjust uses of 'with-machine-lock' to pass the
  'bandwidth hint.

* guix/utils.scm (F_SETLK): New variable.
  (fcntl-flock): Add 'wait?' keyword parameter; honor it.
* tests/utils.scm ("fcntl-flock non-blocking"): New test.

* doc/guix.texi (Invoking guix package): Explain where packages are
  searched for and link to "Package Modules".
  (Defining Packages) <example>: Use 'define-module' clause instead of
  'use-modules'.  Explain why and link to "Package Modules".
  (Invoking guix build): Explain where packages aer searched for and
  link to "Package Modules".
  (Package Modules): Explain that (gnu packages ...) is scanned.

* gnu/packages/pretty-print.scm: New file
* gnu/packages/patches/source-highlight-regexrange-test.patch: New file
* gnu-system.am (dist_patch_DATA): Add patch.
(GNU_SYSTEM_MODULES): Add pretty-print.scm

This fixes a regression introduced in
99fbddf9 ("store: Change 'export-paths'
to always export in topological order.")

* guix/store.scm (export-paths): Define 'ordered' variable.  Iterate
  over it.
* tests/store.scm ("export/import paths, ensure topological order"): Add
  'file0'.  Adjust accordingly.

* gnu/packages/mpd.scm (ncmpc): New variable.

* guix/utils.scm (%libc-errno-pointer, errno): New procedures.
  (fcntl-flock): Use it as the exception's argument.

* guix/scripts/offload.scm (machine-lock-file, lock-machine,
  unlock-machine): New procedures.
  (with-machine-lock): New macro.
  (process-request): Wrap 'send-files' and 'retrieve-files' calls in
  'with-machine-lock'.

* tests/utils.scm (temp-file): New variable.
  ("fcntl-flock"): Rewrite to actually test whether the child process
  waits for the lock to be released.  The previous test was wrong
  because (1) it expected F_SETLK semantics, not F_SETLKW, and (2) it
  got EBADF because of a mismatch between the open mode and the lock
  style.

* guix/download.scm (url-fetch): Pass #:local-build? #t to
  'build-expression->derivation'.
* guix/git-download.scm (git-fetch): Likewise.

* gnu/packages/messaging.scm (bitlbee): New variable.
* gnu/packages/patches/bitlbee-fix-tests.patch: New file.
* gnu/packages/patches/bitlbee-memset-fix.patch: New file.
* gnu-system.am (dist_patch_DATA): Add patches.

* gnu/packages/messaging.scm: New file.
* gnu-system.am (GNU_SYSTEM_MODULES): Add it.

* gnu/packages/gnupg.scm (gnupg-1): New variable.

* gnu/packages/lynx.scm: New file.
* gnu-system.am (GNU_SYSTEM_MODULES): Add it.

* gnu/packages/gnutls.scm (gnutls): Upgrade to 3.2.12.

Co-authored-by: Ludovic Courtès <ludo@gnu.org>

* gnu/packages/python.scm (python2-element-tree, python2-pybugz): New
  variables.

* doc/guix.texi (Invoking guix package): Remove documentation for
  --dry-run, --fallback, --no-substitutes, and --max-silent-time.  Add a
  cross-ref to "Invoking guix build".
  (Invoking guix archive): Add "common build options" as the cross-ref
  topic for "Invoking guix build".
  (Invoking guix build): Move common build options separately.  Add a
  paragraph to explain.

* gnu/packages/version-control.scm (subversion): Update to 1.7.14.

* gnu/packages/version-control.scm (subversion): Add input neon-0.29.6 to
    enable http and https checkouts.