fetestexcept(3m)

1fetestexcept(3M)        Mathematical Library Functions        fetestexcept(3M)
2
3
4

NAME

6       fetestexcept - test floating-point exception flags
7

SYNOPSIS

9       c99 [ flag... ] file... -lm [ library... ]
10       #include <fenv.h>
11
12       int fetestexcept(int excepts);
13
14

DESCRIPTION

16       The  fetestexcept()  function determines which of a specified subset of
17       the floating-point exception flags are currently set. The excepts argu‐
18       ment specifies the floating-point status flags to be queried.
19

RETURN VALUES

21       The  fetestexcept() function returns the value of the bitwise-inclusive
22       OR of the floating-point exception macros  corresponding  to  the  cur‐
23       rently set floating-point exceptions included in excepts.
24

ERRORS

26       No errors are defined.
27

EXAMPLES

29       Example 1 Example using fetestexcept()
30
31
32       The  following  example  calls function f( ) if an invalid exception is
33       set, and then function g( ) if an overflow exception is set:
34
35
36         #include <fenv.h>
37         /* ... */
38         {
39         #     pragma STDC FENV_ACCESS ON
40               int set_excepts;
41               feclearexcept(FE_INVALID | FE_OVERFLOW);
42               // maybe raise exceptions
43               set_excepts = fetestexcept(FE_INVALID | FE_OVERFLOW);
44               if (set_excepts & FE_INVALID) f();
45               if (set_excepts & FE_OVERFLOW) g();
46               /* ... */
47         }
48
49

ATTRIBUTES

51       See attributes(5) for descriptions of the following attributes:
52
53
54
55
56       ┌─────────────────────────────┬─────────────────────────────┐
57       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
58       ├─────────────────────────────┼─────────────────────────────┤
59       │Interface Stability          │Standard                     │
60       ├─────────────────────────────┼─────────────────────────────┤
61       │MT-Level                     │MT-Safe                      │
62       └─────────────────────────────┴─────────────────────────────┘
63