id: don't print context=... when POSIXLY_CORRECT is set

* src/id.c (print_full_info) [POSIXLY_CORRECT]: Don't print context.
Reported by Ulrich Drepper.
* NEWS (Changes in behavior): Mention it.
* doc/coreutils.texi (id invocation): Document that id also prints the
security context, when possible, and when POSIXLY_CORRECT is not set.
* tests/id/no-context: New file.  Test for this.
* tests/Makefile.am (TESTS): Add it.

1 files changed, 4 insertions, 1 deletions

diff --git a/src/id.c b/src/id.c
index b28643b18..ec255e2f8 100644
--- a/src/id.c
+++ b/src/id.c
@@ -328,6 +328,9 @@ print_full_info (const char *username)
     free (groups);
   }
 #endif /* HAVE_GETGROUPS */
-  if (context != NULL)
+
+  /* POSIX mandates the precise output format, and that it not include
+     any context=... part, so skip that if POSIXLY_CORRECT is set.  */
+  if (context != NULL && ! getenv ("POSIXLY_CORRECT"))
     printf (_(" context=%s"), context);
 }