GLib-2.0 ▶ GLib ▶ ascii_strtod

Converts a string to a floating point value.

This function behaves like the standard strtod() function does in the C locale. It does this without actually changing the current locale, since that would not be thread-safe. A limitation of the implementation is that this function will still accept localized versions of infinities and NANs.

This function is typically used when reading configuration files or other non-user input that should be locale independent. To handle input from the user you should normally use the locale-sensitive system strtod() function.

To convert from a gdouble to a string in a locale-insensitive way, use GLib.ascii_dtostr.

If the correct value would cause overflow, plus or minus HUGE_VAL is returned (according to the sign of the value), and ERANGE is stored in errno. If the correct value would cause underflow, a value whose magnitude is no greater than the smallest normalised positive number is returned; whether ERANGE is set is implementation-defined (it may not be set for gradual underflow where a subnormal value is returned).

This function resets errno before calling strtod() so that you can reliably detect overflow and underflow.