1 files changed, 72 insertions, 0 deletions
diff --git a/lib/libc/gen/isinf.3 b/lib/libc/gen/isinf.3
new file mode 100644
index 0000000..02ca3c5
--- /dev/null
+++ b/lib/libc/gen/isinf.3
@@ -0,0 +1,72 @@
+.\" Copyright (c) 1991, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"     @(#)isinf.3	8.2 (Berkeley) 1/29/94
+.\"
+.Dd January 29, 1994
+.Dt ISINF 3
+.Os
+.Sh NAME
+.Nm isinf ,
+.Nm isnan
+.Nd test for infinity or not-a-number
+.Sh SYNOPSIS
+.Ft int 
+.Fn isinf double
+.Ft int 
+.Fn isnan double
+.Sh DESCRIPTION
+The
+.Fn isninf
+function
+returns 1 if the number is
+.Dq \\*(If ,
+otherwise 0.
+.Pp
+The
+.Fn isnan
+function
+returns 1 if the number is
+.Dq not-a-number ,
+otherwise 0.
+.Sh SEE ALSO
+.Xr math 3
+.Rs
+.%T "IEEE Standard for Binary Floating-Point Arithmetic"
+.%Q ANSI
+.%R Std 754-1985
+.Re
+.Sh BUGS
+Neither the
+.Tn VAX
+nor the Tahoe floating point have distinguished values
+for either infinity or not-a-number.
+These routines always return 0 on those architectures.