[src/trunk]: src/lib/libutil Document that errno may be used to distinguish b...

[apb <apb%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/5db8f4fc70ea
branches:  trunk
changeset: 784143:5db8f4fc70ea
user:      apb <apb%NetBSD.org@localhost>
date:      Sat Jan 19 15:28:25 2013 +0000

description:
Document that errno may be used to distinguish between a
non-error result of -1 and an error.

diffstat:

 lib/libutil/parsedate.3 |  16 ++++++++++++++--
 1 files changed, 14 insertions(+), 2 deletions(-)

diffs (39 lines):

diff -r 2273074ab078 -r 5db8f4fc70ea lib/libutil/parsedate.3
--- a/lib/libutil/parsedate.3   Sat Jan 19 15:25:58 2013 +0000
+++ b/lib/libutil/parsedate.3   Sat Jan 19 15:28:25 2013 +0000
@@ -1,4 +1,4 @@
-.\"     $NetBSD: parsedate.3,v 1.11 2012/04/06 11:36:04 wiz Exp $
+.\"     $NetBSD: parsedate.3,v 1.12 2013/01/19 15:28:25 apb Exp $
 .\"
 .\" Copyright (c) 2006 The NetBSD Foundation, Inc.
 .\" All rights reserved.
@@ -27,7 +27,7 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 .\" POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd December 20, 2010
+.Dd January 19, 2013
 .Dt PARSEDATE 3
 .Os
 .Sh NAME
@@ -241,8 +241,20 @@
 returns the number of seconds passed since the Epoch, or
 .Dv \-1
 if the date could not be parsed properly.
+A non-error result of
+.Dv \-1
+can be distinguished from an error by setting
+.Va errno
+to
+.Dv 0
+before calling
+.Fn parsedate ,
+and checking the value of
+.Va errno
+afterwards.
 .Sh SEE ALSO
 .Xr date 1 ,
+.Xr errno 2 ,
 .Xr eeprom 8
 .Sh HISTORY
 The parser used in