syscalls: Add utmpx procedures and data structure.

* guix/build/syscalls.scm (<utmpx-entry>): New record type.
(%utmpx): New C struct.
(login-type): New bits.
(setutxent, endutxent, getutxent, utmpx-entries): New procedures.

1 files changed, 12 insertions, 1 deletions

diff --git a/tests/syscalls.scm b/tests/syscalls.scm
index e4ef32c522c..fb2c8e71004 100644
--- a/tests/syscalls.scm
+++ b/tests/syscalls.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2014, 2015, 2016 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2014, 2015, 2016, 2017 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2015 David Thompson <davet@gnu.org>
 ;;;
 ;;; This file is part of GNU Guix.
@@ -441,6 +441,17 @@
   (> (terminal-columns (open-input-string "Join us now, share the software!"))
      0))
 
+(test-assert "utmpx-entries"
+  (match (utmpx-entries)
+    (((? utmpx? entries) ...)
+     (every (lambda (entry)
+              (match (utmpx-user entry)
+                ((? string?)
+                 (> (utmpx-pid entry) 0))
+                (#f                               ;might be DEAD_PROCESS
+                 #t)))
+            entries))))
+
 (test-end)
 
 (false-if-exception (delete-file temp-file))