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-rw-r--r--man3/signbit.315
1 files changed, 7 insertions, 8 deletions
diff --git a/man3/signbit.3 b/man3/signbit.3
index 5dddad6..ad7a1f4 100644
--- a/man3/signbit.3
+++ b/man3/signbit.3
@@ -7,7 +7,7 @@
.\"
.\" Based on glibc infopages, copyright Free Software Foundation
.\"
-.TH signbit 3 2023-07-20 "Linux man-pages 6.05.01"
+.TH signbit 3 2023-10-31 "Linux man-pages 6.7"
.SH NAME
signbit \- test sign of a real floating-point number
.SH LIBRARY
@@ -16,15 +16,15 @@ Math library
.SH SYNOPSIS
.nf
.B "#include <math.h>"
-.PP
+.P
.BI "int signbit(" x ");"
.fi
-.PP
+.P
.RS -4
Feature Test Macro Requirements for glibc (see
.BR feature_test_macros (7)):
.RE
-.PP
+.P
.BR signbit ():
.nf
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
@@ -35,7 +35,7 @@ is a generic macro which can work on all real floating-point types.
It returns a nonzero value if the value of
.I x
has its sign bit set.
-.PP
+.P
This is not the same as
.IR "x < 0.0" ,
because IEEE 754 floating point allows zero to be signed.
@@ -44,7 +44,7 @@ The comparison
is false, but
.I signbit(\-0.0)
will return a nonzero value.
-.PP
+.P
NaNs and infinities have a sign bit.
.SH RETURN VALUE
The
@@ -68,12 +68,11 @@ T{
.BR signbit ()
T} Thread safety MT-Safe
.TE
-.sp 1
.SH STANDARDS
C11, POSIX.1-2008.
.SH HISTORY
POSIX.1-2001, C99.
-.PP
+.P
This function is defined in IEC 559 (and the appendix with
recommended functions in IEEE 754/IEEE 854).
.SH SEE ALSO