1 .\" Copyright 2004 Andries Brouwer <aeb@cwi.nl>.
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23 .TH FINITE 3 2008-08-05 "" "Linux Programmer's Manual"
25 finite, finitef, finitel, isinf, isinff, isinfl, isnan, isnanf, isnanl \-
26 BSD floating-point classification functions
31 .BI "int finite(double " x );
33 .BI "int finitef(float " x );
35 .BI "int finitel(long double " x );
37 .BI "int isinf(double " x );
39 .BI "int isinff(float " x );
41 .BI "int isinfl(long double " x );
43 .BI "int isnan(double " x );
45 .BI "int isnanf(float " x );
47 .BI "int isnanl(long double " x );
51 Feature Test Macro Requirements for glibc (see
52 .BR feature_test_macros (7)):
59 _BSD_SOURCE || _SVID_SOURCE
62 _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE\ >=\ 600 || _ISOC99_SOURCE;
67 _BSD_SOURCE || _SVID_SOURCE
70 _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE || _ISOC99_SOURCE;
75 _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE\ >=\ 600
80 functions return a nonzero value if \fIx\fP is neither infinite
81 nor a "not-a-number" (NaN) value, and 0 otherwise.
85 functions return a nonzero value if \fIx\fP is a NaN value,
90 functions return 1 if \fIx\fP is positive infinity, \-1 if \fIx\fP
91 is negative infinity, and 0 otherwise.
93 Note that these functions are obsolete.
99 (for all types) replacing them.
100 Further note that the C99
102 has weaker guarantees on the return value.
106 .\" finite* not on HP-UX; they exist on Tru64.
110 .\" function occurs in 4.3BSD.
111 .\" see IEEE.3 in the 4.3BSD manual