Tcl_PrintDouble - Man Page

#include <tcl.h>

Tcl_PrintDouble(interp, value, dst)

Tcl_Interp *interp (in)

This argument is ignored.

double value (in)

Floating-point value to be converted.

char *dst (out)

Where to store the string representing value.  Must have at least TCL_DOUBLE_SPACE characters of storage.

Tcl_PrintDouble generates a string that represents the value of value and stores it in memory at the location given by dst.  It uses %g format to generate the string, with one special twist: the string is guaranteed to contain either a “.” or an “e” so that it does not look like an integer.  Where %g would generate an integer with no decimal point, Tcl_PrintDouble adds “.0”.

The result will have the fewest digits needed to represent the number in such a way that Tcl_NewDoubleObj will generate the same number when presented with the given string. IEEE semantics of rounding to even apply to the conversion.

conversion, double-precision, floating-point, string