Clarify a bit.

1 files changed, 16 insertions, 6 deletions

diff --git a/lib/libc/gen/err.3 b/lib/libc/gen/err.3
index 508e7edbc85..9867ddb2cc9 100644
--- a/lib/libc/gen/err.3
+++ b/lib/libc/gen/err.3
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: err.3,v 1.3 1997/05/30 07:48:23 deraadt Exp $
+.\"	$OpenBSD: err.3,v 1.4 1997/08/08 23:14:51 millert Exp $
 .\"
 .\" Copyright (c) 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -31,7 +31,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd June, 9, 1993
+.Dd August, 8, 1997
 .Dt ERR 3
 .Os BSD 4
 .Sh NAME
@@ -74,14 +74,19 @@ and a space are output.
 If the
 .Va fmt
 argument is not NULL, the formatted error message, a colon character,
-and a space are output.
+and a space are output.  The
+.Va fmt
+argument (and associated arguments) may be any format allowed by
+.Xr printf 3
+or a simple string.
+.Pp
 In the case of the
 .Fn err ,
 .Fn verr ,
 .Fn warn ,
 and
 .Fn vwarn
-functions, the error message string affiliated with the current value of
+functions only, the error message string affiliated with the current value of
 the global variable
 .Va errno 
 is output.
@@ -96,12 +101,14 @@ and
 functions do not return, but exit with the value of the argument
 .Fa eval .
 .Sh EXAMPLES
-Display the current errno information string and exit:
+Display the current
+.Va errno
+information string and exit:
 .Bd -literal -offset indent
 if ((p = malloc(size)) == NULL)
 	err(1, NULL);
 if ((fd = open(file_name, O_RDONLY, 0)) == -1)
-	err(1, "%s", file_name);
+	err(1, file_name);
 .Ed
 .Pp
 Display an error message and exit:
@@ -119,6 +126,9 @@ if ((fd = open(block_device, O_RDONLY, 0)) == -1)
 	err(1, "%s", block_device);
 .Ed
 .Sh SEE ALSO
+.Xr exit 3 ,
+.Xr perror 3 ,
+.Xr printf 3 ,
 .Xr strerror 3
 .Sh HISTORY
 The