## Linux and UNIX Man Pages

Test Your Knowledge in Computers #882
Difficulty: Easy
In October 2013 National Geographic released a file titled American Blackout which dealt with an imagined large-scale cyber attack on SCADA and the US electrical grid.
True or False?

# copysign(3m) [sunos man page]

```copysign(3M)						  Mathematical Library Functions					      copysign(3M)

NAME
copysign, copysignf, copysignl - number manipulation function

SYNOPSIS
cc [ flag... ] file... -lm [ library... ]
#include <math.h>

double copysign(double x, double y);

float copysignf(float x, float y);

long double copysignl(long double x, long double y);

DESCRIPTION
These functions produce a value with the magnitude of x and the sign of y.

RETURN VALUES
Upon successful completion, these functions return a value with the magnitude of x and the sign of y.

ERRORS
No errors are defined.

ATTRIBUTES
See attributes(5) for descriptions of the following attributes:

+-----------------------------+-----------------------------+
|      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
+-----------------------------+-----------------------------+
|Interface Stability	     |Standard			   |
+-----------------------------+-----------------------------+
|MT-Level		     |MT-Safe			   |
+-----------------------------+-----------------------------+

SunOS 5.10							    1 Sep 2002							      copysign(3M)```

## Check Out this Related Man Page

```copysign(3M)						  Mathematical Library Functions					      copysign(3M)

NAME
copysign, copysignf, copysignl - number manipulation function

SYNOPSIS
c99 [ flag... ] file... -lm [ library... ]
#include <math.h>

double copysign(double x, double y);

float copysignf(float x, float y);

long double copysignl(long double x, long double y);

DESCRIPTION
These functions produce a value with the magnitude of x and the sign of y.

RETURN VALUES
Upon successful completion, these functions return a value with the magnitude of x and the sign of y.

ERRORS
No errors are defined.

ATTRIBUTES
See attributes(5) for descriptions of the following attributes:

+-----------------------------+-----------------------------+
|      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
+-----------------------------+-----------------------------+
|Interface Stability	     |Standard			   |
+-----------------------------+-----------------------------+
|MT-Level		     |MT-Safe			   |
+-----------------------------+-----------------------------+