pdfSetCharacterSpacing

double __stdcall pdfGetCharacterSpacing(PPDF IPDF);
BOOL32 __stdcall pdfSetCharacterSpacing(PPDF IPDF, double Value);
double __stdcall pdfGetWordSpacing(PPDF IPDF);
BOOL32 __stdcall pdfSetWordSpacing(PPDF IPDF, double Value);

function pdfGetCharacterSpacing(const IPDF: PPDF): Double; stdcall;
function pdfSetCharacterSpacing(const IPDF: PPDF; Value: Double): LongBool; stdcall;
function pdfGetWordSpacing(const IPDF: PPDF): Double; stdcall;
function pdfSetWordSpacing(const IPDF: PPDF; Value: Double): LongBool; stdcall;

Purpose. Set/get the PDF Tc (character spacing) and Tw (word spacing) text-state parameters.

Description. Both setters are real: they cache the value and immediately emit the corresponding Tc/Tw content-stream operator via the current content stream, taking effect on subsequently-written text.

Return value. Getters: the cached current value; 0.0 if IPDF invalid. Setters: True if there is a current content stream to write into; False otherwise.

C# (P/Invoke)

[return: MarshalAs(UnmanagedType.Bool)]