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Tcl_PrintDouble(3tcl) Tcl Library Procedures Tcl_PrintDouble(3tcl)


Tcl_PrintDouble - Convert floating value to string


#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

8.0 Tcl