Section (3) fabs
fabs, fabsf, fabsl — absolute value of floating-point number
||long double x
These functions return the absolute value of
x is a NaN, a
NaN is returned.
x is −0,
+0 is returned.
x is negative
infinity or positive infinity, positive infinity is
For an explanation of the terms used in this section, see attributes(7).
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning double also conforms to SVr4, 4.3BSD, C89.
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Copyright 1993 David Metcalfe (davidprism.demon.co.uk)
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Linux libc source code
Lewine_zsingle_quotesz_s _POSIX Programmer_zsingle_quotesz_s Guide_ (O_zsingle_quotesz_Reilly & Associates, 1991)
386BSD man pages
Modified Sat Jul 24 19:42:04 1993 by Rik Faith (faithcs.unc.edu)
Added fabsl, fabsf, aeb, 2001-06-07