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Defined in header <wchar.h> | ||
float wcstof(constwchar_t*restrict str,wchar_t**restrict str_end); | (since C99) | |
double wcstod(constwchar_t* str,wchar_t** str_end); | (since C95) (until C99) | |
double wcstod(constwchar_t*restrict str,wchar_t**restrict str_end); | (since C99) | |
longdouble wcstold(constwchar_t*restrict str,wchar_t**restrict str_end); | (since C99) | |
Interprets a floating-point value in a wide string pointed to bystr.
Function discards any whitespace characters (as determined byiswspace) until first non-whitespace character is found. Then it takes as many characters as possible to form a valid floating-point representation and converts them to a floating-point value. The valid floating-point value can be one of the following:
e orE followed with optional minus or plus sign and nonempty sequence of decimal digits (defines exponent to base10)
| (since C99) |
The functions sets the pointer pointed to bystr_end to point to the wide character past the last character interpreted. Ifstr_end is a null pointer, it is ignored.
Contents |
| str | - | pointer to the null-terminated wide string to be interpreted |
| str_end | - | pointer to a pointer to a wide character. |
Floating-point value corresponding to the contents ofstr on success. If the converted value falls out of range of corresponding return type, range error occurs andHUGE_VAL,HUGE_VALF orHUGE_VALL is returned. If no conversion can be performed,0 is returned.
#include <errno.h>#include <stdio.h>#include <wchar.h> int main(void){constwchar_t* p= L"111.11 -2.22 0X1.BC70A3D70A3D7P+6 1.18973e+4932zzz";printf("Parsing L\"%ls\":\n", p);wchar_t* end;for(double f= wcstod(p,&end); p!= end; f= wcstod(p,&end)){printf("'%.*ls' -> ",(int)(end-p), p); p= end;if(errno==ERANGE){printf("range error, got ");errno=0;}printf("%f\n", f);}}
Output:
Parsing L"111.11 -2.22 0X1.BC70A3D70A3D7P+6 1.18973e+4932zzz":'111.11' -> 111.110000' -2.22' -> -2.220000' 0X1.BC70A3D70A3D7P+6' -> 111.110000' 1.18973e+4932' -> range error, got inf
(C99)(C99) | converts a byte string to a floating-point value (function)[edit] |
C++ documentation forwcstof,wcstod,wcstold | |
