atof
convert <span class="Tn">ASCII</span> string to double
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INTERFACE
#include <stdlib.h> double atof ( const char *nptr ) #include <xlocale.h> double atof_l ( const char *nptr, locale_t loc )
DESCRIPTION
The atof function converts the initial portion of the string pointed to by nptr to double representation. It is equivalent to:
strtod(nptr, (char **)NULL);The decimal point character is defined in the program's locale (category LC_NUMERIC). While the atof function uses the current locale, the atof_l function may be passed a locale directly. See xlocale for more information.
Example 1
#include <stdio.h>
#include <stdlib.h>
int main()
{
char x[10] = "3.141592";
double pi = atof(x);
printf("pi = %lf\n", pi);
return 0;
}Output:
pi = 3.141592IMPLEMENTATION NOTES
The atof function is not thread-safe and also not async-cancel-safe.
The atof function has been deprecated by strtod and should not be used in new code.
ERRORS
The function atof need not affect the value of errno on an error.